Remove compile warning
diff --git a/MagickCore/annotate.c b/MagickCore/annotate.c
index 0b9d3b3..a8cd0aa 100644
--- a/MagickCore/annotate.c
+++ b/MagickCore/annotate.c
@@ -1035,10 +1035,10 @@
   register size_t
     i;
 
-  ssize_t
-    count;
+  size_t
+    extent;
 
-  count=0;
+  extent=0;
   rq=raqm_create();
   if (rq == (raqm_t *) NULL)
     goto cleanup;
@@ -1079,19 +1079,19 @@
     }
   if (raqm_layout(rq) == 0)
     goto cleanup;
-  glyphs=raqm_get_glyphs(rq,&count);
+  glyphs=raqm_get_glyphs(rq,&extent);
   if (glyphs == (raqm_glyph_t *) NULL)
     {
-      count=0;
+      extent=0;
       goto cleanup;
     }
-  *grapheme=(GraphemeInfo *) AcquireQuantumMemory(count,sizeof(**grapheme));
+  *grapheme=(GraphemeInfo *) AcquireQuantumMemory(extent,sizeof(**grapheme));
   if (*grapheme == (GraphemeInfo *) NULL)
     {
-      count=0;
+      extent=0;
       goto cleanup;
     }
-  for (i=0; i < (ssize_t) count; i++)
+  for (i=0; i < (ssize_t) extent; i++)
   {
     (*grapheme)[i].index=glyphs[i].index;
     (*grapheme)[i].x_offset=glyphs[i].x_offset;
@@ -1102,7 +1102,7 @@
 
 cleanup:
   raqm_destroy(rq);
-  return(count);
+  return(extent);
 #else
   const char
     *p;
diff --git a/Makefile.am b/Makefile.am
index 4f96202..33406e2 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -292,7 +292,7 @@
 	$(SHELL) ./config.status --recheck
 
 # Format C API documentation
-html:
+html-local:
 # copy static file
 	for dir in $(DOCDIRSMANUAL) ; do \
 		$(MKDIR_P) $(top_builddir)/$$dir ;\
diff --git a/Makefile.in b/Makefile.in
index 96edf43..be21306 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -2037,7 +2037,7 @@
 am__v_at_ = $(am__v_at_@AM_DEFAULT_V@)
 am__v_at_0 = @
 am__v_at_1 = 
-DEFAULT_INCLUDES = 
+DEFAULT_INCLUDES = -I.@am__isrc@ -I$(top_builddir)/config
 depcomp = $(SHELL) $(top_srcdir)/config/depcomp
 am__depfiles_maybe = depfiles
 am__mv = mv -f
@@ -2556,10 +2556,9 @@
       || { sleep 5 && rm -rf "$(distdir)"; }; \
   else :; fi
 am__post_remove_distdir = $(am__remove_distdir)
-DIST_ARCHIVES = $(distdir).tar.gz $(distdir).tar.bz2 $(distdir).tar.lz \
-	$(distdir).tar.xz $(distdir).zip
+DIST_ARCHIVES = $(distdir).tar.gz
 GZIP_ENV = --best
-DIST_TARGETS = dist-lzip dist-xz dist-bzip2 dist-gzip dist-zip
+DIST_TARGETS = dist-gzip
 distuninstallcheck_listfiles = find . -type f -print
 am__distuninstallcheck_listfiles = $(distuninstallcheck_listfiles) \
   | sed 's|^\./|$(prefix)/|' | grep -v '$(infodir)/dir$$'
@@ -2875,6 +2874,10 @@
 UMEM_LIBS = @UMEM_LIBS@
 UniconvertorDelegate = @UniconvertorDelegate@
 VERSION = @VERSION@
+WARN_CFLAGS = @WARN_CFLAGS@
+WARN_CXXFLAGS = @WARN_CXXFLAGS@
+WARN_LDFLAGS = @WARN_LDFLAGS@
+WARN_SCANNERFLAGS = @WARN_SCANNERFLAGS@
 WEBP_LIBS = @WEBP_LIBS@
 WMFDecodeDelegate = @WMFDecodeDelegate@
 WMF_CFLAGS = @WMF_CFLAGS@
@@ -11346,12 +11349,15 @@
 dist-gzip: distdir
 	tardir=$(distdir) && $(am__tar) | GZIP=$(GZIP_ENV) gzip -c >$(distdir).tar.gz
 	$(am__post_remove_distdir)
+
 dist-bzip2: distdir
 	tardir=$(distdir) && $(am__tar) | BZIP2=$${BZIP2--9} bzip2 -c >$(distdir).tar.bz2
 	$(am__post_remove_distdir)
+
 dist-lzip: distdir
 	tardir=$(distdir) && $(am__tar) | lzip -c $${LZIP_OPT--9} >$(distdir).tar.lz
 	$(am__post_remove_distdir)
+
 dist-xz: distdir
 	tardir=$(distdir) && $(am__tar) | XZ_OPT=$${XZ_OPT--e} xz -c >$(distdir).tar.xz
 	$(am__post_remove_distdir)
@@ -11369,6 +11375,7 @@
 	@echo WARNING: "It will be removed altogether in Automake 2.0" >&2
 	shar $(distdir) | GZIP=$(GZIP_ENV) gzip -c >$(distdir).shar.gz
 	$(am__post_remove_distdir)
+
 dist-zip: distdir
 	-rm -f $(distdir).zip
 	zip -rq $(distdir).zip $(distdir)
@@ -11550,7 +11557,9 @@
 
 dvi-am:
 
-html-am:
+html: html-am
+
+html-am: html-local
 
 info: info-am
 
@@ -11638,8 +11647,8 @@
 	dist-zip distcheck distclean distclean-compile \
 	distclean-generic distclean-hdr distclean-libtool \
 	distclean-local distclean-tags distcleancheck distdir \
-	distuninstallcheck dvi dvi-am html html-am info info-am \
-	install install-MagickCoreincHEADERS \
+	distuninstallcheck dvi dvi-am html html-am html-local info \
+	info-am install install-MagickCoreincHEADERS \
 	install-MagickCoreincarchHEADERS install-MagickWandincHEADERS \
 	install-am install-binPROGRAMS install-binSCRIPTS \
 	install-codersLTLIBRARIES install-configlibDATA \
@@ -11869,7 +11878,7 @@
 	$(SHELL) ./config.status --recheck
 
 # Format C API documentation
-html:
+html-local:
 # copy static file
 	for dir in $(DOCDIRSMANUAL) ; do \
 		$(MKDIR_P) $(top_builddir)/$$dir ;\
diff --git a/aclocal.m4 b/aclocal.m4
index 24f9616..3aec86f 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -20,6 +20,771 @@
 If you have problems, you may need to regenerate the build system entirely.
 To do so, use the procedure documented by the package, typically 'autoreconf'.])])
 
+# ===========================================================================
+#  http://www.gnu.org/software/autoconf-archive/ax_append_compile_flags.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_APPEND_COMPILE_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS])
+#
+# DESCRIPTION
+#
+#   For every FLAG1, FLAG2 it is checked whether the compiler works with the
+#   flag.  If it does, the flag is added FLAGS-VARIABLE
+#
+#   If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
+#   CFLAGS) is used.  During the check the flag is always added to the
+#   current language's flags.
+#
+#   If EXTRA-FLAGS is defined, it is added to the current language's default
+#   flags (e.g. CFLAGS) when the check is done.  The check is thus made with
+#   the flags: "CFLAGS EXTRA-FLAGS FLAG".  This can for example be used to
+#   force the compiler to issue an error when a bad flag is given.
+#
+#   NOTE: This macro depends on the AX_APPEND_FLAG and
+#   AX_CHECK_COMPILE_FLAG. Please keep this macro in sync with
+#   AX_APPEND_LINK_FLAGS.
+#
+# LICENSE
+#
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 4
+
+AC_DEFUN([AX_APPEND_COMPILE_FLAGS],
+[AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
+AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+for flag in $1; do
+  AX_CHECK_COMPILE_FLAG([$flag], [AX_APPEND_FLAG([$flag], [$2])], [], [$3])
+done
+])dnl AX_APPEND_COMPILE_FLAGS
+
+# ===========================================================================
+#   http://www.gnu.org/software/autoconf-archive/ax_append_link_flags.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_APPEND_LINK_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS])
+#
+# DESCRIPTION
+#
+#   For every FLAG1, FLAG2 it is checked whether the linker works with the
+#   flag.  If it does, the flag is added FLAGS-VARIABLE
+#
+#   If FLAGS-VARIABLE is not specified, the linker's flags (LDFLAGS) is
+#   used. During the check the flag is always added to the linker's flags.
+#
+#   If EXTRA-FLAGS is defined, it is added to the linker's default flags
+#   when the check is done.  The check is thus made with the flags: "LDFLAGS
+#   EXTRA-FLAGS FLAG".  This can for example be used to force the linker to
+#   issue an error when a bad flag is given.
+#
+#   NOTE: This macro depends on the AX_APPEND_FLAG and AX_CHECK_LINK_FLAG.
+#   Please keep this macro in sync with AX_APPEND_COMPILE_FLAGS.
+#
+# LICENSE
+#
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 4
+
+AC_DEFUN([AX_APPEND_LINK_FLAGS],
+[AX_REQUIRE_DEFINED([AX_CHECK_LINK_FLAG])
+AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+for flag in $1; do
+  AX_CHECK_LINK_FLAG([$flag], [AX_APPEND_FLAG([$flag], [m4_default([$2], [LDFLAGS])])], [], [$3])
+done
+])dnl AX_APPEND_LINK_FLAGS
+
+# ===========================================================================
+#    http://www.gnu.org/software/autoconf-archive/ax_check_link_flag.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
+#
+# DESCRIPTION
+#
+#   Check whether the given FLAG works with the linker or gives an error.
+#   (Warnings, however, are ignored)
+#
+#   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
+#   success/failure.
+#
+#   If EXTRA-FLAGS is defined, it is added to the linker's default flags
+#   when the check is done.  The check is thus made with the flags: "LDFLAGS
+#   EXTRA-FLAGS FLAG".  This can for example be used to force the linker to
+#   issue an error when a bad flag is given.
+#
+#   INPUT gives an alternative input source to AC_LINK_IFELSE.
+#
+#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
+#   macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 4
+
+AC_DEFUN([AX_CHECK_LINK_FLAG],
+[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
+AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
+AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
+  ax_check_save_flags=$LDFLAGS
+  LDFLAGS="$LDFLAGS $4 $1"
+  AC_LINK_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
+    [AS_VAR_SET(CACHEVAR,[yes])],
+    [AS_VAR_SET(CACHEVAR,[no])])
+  LDFLAGS=$ax_check_save_flags])
+AS_VAR_IF(CACHEVAR,yes,
+  [m4_default([$2], :)],
+  [m4_default([$3], :)])
+AS_VAR_POPDEF([CACHEVAR])dnl
+])dnl AX_CHECK_LINK_FLAGS
+
+# ===========================================================================
+#     http://www.gnu.org/software/autoconf-archive/ax_compiler_flags.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_COMPILER_FLAGS([CFLAGS-VARIABLE], [LDFLAGS-VARIABLE], [IS-RELEASE], [EXTRA-BASE-CFLAGS], [EXTRA-YES-CFLAGS], [UNUSED], [UNUSED], [UNUSED], [EXTRA-BASE-LDFLAGS], [EXTRA-YES-LDFLAGS], [UNUSED], [UNUSED], [UNUSED])
+#
+# DESCRIPTION
+#
+#   Check for the presence of an --enable-compile-warnings option to
+#   configure, defaulting to "error" in normal operation, or "yes" if
+#   IS-RELEASE is equal to "yes".  Return the value in the variable
+#   $ax_enable_compile_warnings.
+#
+#   Depending on the value of --enable-compile-warnings, different compiler
+#   warnings are checked to see if they work with the current compiler and,
+#   if so, are appended to CFLAGS-VARIABLE and LDFLAGS-VARIABLE.  This
+#   allows a consistent set of baseline compiler warnings to be used across
+#   a code base, irrespective of any warnings enabled locally by individual
+#   developers.  By standardising the warnings used by all developers of a
+#   project, the project can commit to a zero-warnings policy, using -Werror
+#   to prevent compilation if new warnings are introduced.  This makes
+#   catching bugs which are flagged by warnings a lot easier.
+#
+#   By providing a consistent --enable-compile-warnings argument across all
+#   projects using this macro, continuous integration systems can easily be
+#   configured the same for all projects.  Automated systems or build
+#   systems aimed at beginners may want to pass the --disable-Werror
+#   argument to unconditionally prevent warnings being fatal.
+#
+#   --enable-compile-warnings can take the values:
+#
+#    * no:      Base compiler warnings only; not even -Wall.
+#    * yes:     The above, plus a broad range of useful warnings.
+#    * error:   The above, plus -Werror so that all warnings are fatal.
+#               Use --disable-Werror to override this and disable fatal
+#               warnings.
+#
+#   The set of base and enabled flags can be augmented using the
+#   EXTRA-*-CFLAGS and EXTRA-*-LDFLAGS variables, which are tested and
+#   appended to the output variable if --enable-compile-warnings is not
+#   "no". Flags should not be disabled using these arguments, as the entire
+#   point of AX_COMPILER_FLAGS is to enforce a consistent set of useful
+#   compiler warnings on code, using warnings which have been chosen for low
+#   false positive rates.  If a compiler emits false positives for a
+#   warning, a #pragma should be used in the code to disable the warning
+#   locally. See:
+#
+#     https://gcc.gnu.org/onlinedocs/gcc-4.9.2/gcc/Diagnostic-Pragmas.html#Diagnostic-Pragmas
+#
+#   The EXTRA-* variables should only be used to supply extra warning flags,
+#   and not general purpose compiler flags, as they are controlled by
+#   configure options such as --disable-Werror.
+#
+#   IS-RELEASE can be used to disable -Werror when making a release, which
+#   is useful for those hairy moments when you just want to get the release
+#   done as quickly as possible.  Set it to "yes" to disable -Werror. By
+#   default, it uses the value of $ax_is_release, so if you are using the
+#   AX_IS_RELEASE macro, there is no need to pass this parameter. For
+#   example:
+#
+#     AX_IS_RELEASE([git-directory])
+#     AX_COMPILER_FLAGS()
+#
+#   CFLAGS-VARIABLE defaults to WARN_CFLAGS, and LDFLAGS-VARIABLE defaults
+#   to WARN_LDFLAGS.  Both variables are AC_SUBST-ed by this macro, but must
+#   be manually added to the CFLAGS and LDFLAGS variables for each target in
+#   the code base.
+#
+#   If C++ language support is enabled with AC_PROG_CXX, which must occur
+#   before this macro in configure.ac, warning flags for the C++ compiler
+#   are AC_SUBST-ed as WARN_CXXFLAGS, and must be manually added to the
+#   CXXFLAGS variables for each target in the code base.  EXTRA-*-CFLAGS can
+#   be used to augment the base and enabled flags.
+#
+#   Warning flags for g-ir-scanner (from GObject Introspection) are
+#   AC_SUBST-ed as WARN_SCANNERFLAGS.  This variable must be manually added
+#   to the SCANNERFLAGS variable for each GIR target in the code base.  If
+#   extra g-ir-scanner flags need to be enabled, the AX_COMPILER_FLAGS_GIR
+#   macro must be invoked manually.
+#
+#   AX_COMPILER_FLAGS may add support for other tools in future, in addition
+#   to the compiler and linker.  No extra EXTRA-* variables will be added
+#   for those tools, and all extra support will still use the single
+#   --enable-compile-warnings configure option.  For finer grained control
+#   over the flags for individual tools, use AX_COMPILER_FLAGS_CFLAGS,
+#   AX_COMPILER_FLAGS_LDFLAGS and AX_COMPILER_FLAGS_* for new tools.
+#
+#   The UNUSED variables date from a previous version of this macro, and are
+#   automatically appended to the preceding non-UNUSED variable. They should
+#   be left empty in new uses of the macro.
+#
+# LICENSE
+#
+#   Copyright (c) 2014, 2015 Philip Withnall <philip@tecnocode.co.uk>
+#   Copyright (c) 2015 David King <amigadave@amigadave.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 13
+
+# _AX_COMPILER_FLAGS_LANG([LANGNAME])
+m4_defun([_AX_COMPILER_FLAGS_LANG],
+[m4_ifdef([_AX_COMPILER_FLAGS_LANG_]$1[_enabled], [],
+          [m4_define([_AX_COMPILER_FLAGS_LANG_]$1[_enabled], [])dnl
+           AX_REQUIRE_DEFINED([AX_COMPILER_FLAGS_]$1[FLAGS])])dnl
+])
+
+AC_DEFUN([AX_COMPILER_FLAGS],[
+    # C support is enabled by default.
+    _AX_COMPILER_FLAGS_LANG([C])
+    # Only enable C++ support if AC_PROG_CXX is called. The redefinition of
+    # AC_PROG_CXX is so that a fatal error is emitted if this macro is called
+    # before AC_PROG_CXX, which would otherwise cause no C++ warnings to be
+    # checked.
+    AC_PROVIDE_IFELSE([AC_PROG_CXX],
+                      [_AX_COMPILER_FLAGS_LANG([CXX])],
+                      [m4_define([AC_PROG_CXX], defn([AC_PROG_CXX])[_AX_COMPILER_FLAGS_LANG([CXX])])])
+    AX_REQUIRE_DEFINED([AX_COMPILER_FLAGS_LDFLAGS])
+
+    # Default value for IS-RELEASE is $ax_is_release
+    ax_compiler_flags_is_release=m4_tolower(m4_normalize(ifelse([$3],,
+                                                                [$ax_is_release],
+                                                                [$3])))
+
+    AC_ARG_ENABLE([compile-warnings],
+                  AS_HELP_STRING([--enable-compile-warnings=@<:@no/yes/error@:>@],
+                                 [Enable compiler warnings and errors]),,
+                  [AS_IF([test "$ax_compiler_flags_is_release" = "yes"],
+                         [enable_compile_warnings="yes"],
+                         [enable_compile_warnings="error"])])
+    AC_ARG_ENABLE([Werror],
+                  AS_HELP_STRING([--disable-Werror],
+                                 [Unconditionally make all compiler warnings non-fatal]),,
+                  [enable_Werror=maybe])
+
+    # Return the user's chosen warning level
+    AS_IF([test "$enable_Werror" = "no" -a \
+                "$enable_compile_warnings" = "error"],[
+        enable_compile_warnings="yes"
+    ])
+
+    ax_enable_compile_warnings=$enable_compile_warnings
+
+    AX_COMPILER_FLAGS_CFLAGS([$1],[$ax_compiler_flags_is_release],
+                             [$4],[$5 $6 $7 $8])
+    m4_ifdef([_AX_COMPILER_FLAGS_LANG_CXX_enabled],
+             [AX_COMPILER_FLAGS_CXXFLAGS([WARN_CXXFLAGS],
+                                         [$ax_compiler_flags_is_release],
+                                         [$4],[$5 $6 $7 $8])])
+    AX_COMPILER_FLAGS_LDFLAGS([$2],[$ax_compiler_flags_is_release],
+                              [$9],[$10 $11 $12 $13])
+    AX_COMPILER_FLAGS_GIR([WARN_SCANNERFLAGS],[$ax_compiler_flags_is_release])
+])dnl AX_COMPILER_FLAGS
+
+# ============================================================================
+#  http://www.gnu.org/software/autoconf-archive/ax_compiler_flags_cflags.html
+# ============================================================================
+#
+# SYNOPSIS
+#
+#   AX_COMPILER_FLAGS_CFLAGS([VARIABLE], [IS-RELEASE], [EXTRA-BASE-FLAGS], [EXTRA-YES-FLAGS])
+#
+# DESCRIPTION
+#
+#   Add warning flags for the C compiler to VARIABLE, which defaults to
+#   WARN_CFLAGS.  VARIABLE is AC_SUBST-ed by this macro, but must be
+#   manually added to the CFLAGS variable for each target in the code base.
+#
+#   This macro depends on the environment set up by AX_COMPILER_FLAGS.
+#   Specifically, it uses the value of $ax_enable_compile_warnings to decide
+#   which flags to enable.
+#
+# LICENSE
+#
+#   Copyright (c) 2014, 2015 Philip Withnall <philip@tecnocode.co.uk>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 11
+
+AC_DEFUN([AX_COMPILER_FLAGS_CFLAGS],[
+    AC_REQUIRE([AC_PROG_SED])
+    AX_REQUIRE_DEFINED([AX_APPEND_COMPILE_FLAGS])
+    AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+    AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
+
+    # Variable names
+    m4_define(ax_warn_cflags_variable,
+              [m4_normalize(ifelse([$1],,[WARN_CFLAGS],[$1]))])
+
+    AC_LANG_PUSH([C])
+
+    # Always pass -Werror=unknown-warning-option to get Clang to fail on bad
+    # flags, otherwise they are always appended to the warn_cflags variable, and
+    # Clang warns on them for every compilation unit.
+    # If this is passed to GCC, it will explode, so the flag must be enabled
+    # conditionally.
+    AX_CHECK_COMPILE_FLAG([-Werror=unknown-warning-option],[
+        ax_compiler_flags_test="-Werror=unknown-warning-option"
+    ],[
+        ax_compiler_flags_test=""
+    ])
+
+    # Base flags
+    AX_APPEND_COMPILE_FLAGS([ dnl
+        -fno-strict-aliasing dnl
+        $3 dnl
+    ],ax_warn_cflags_variable,[$ax_compiler_flags_test])
+
+    AS_IF([test "$ax_enable_compile_warnings" != "no"],[
+        # "yes" flags
+        AX_APPEND_COMPILE_FLAGS([ dnl
+            -Wall dnl
+            -Wextra dnl
+            -Wundef dnl
+            -Wnested-externs dnl
+            -Wwrite-strings dnl
+            -Wpointer-arith dnl
+            -Wmissing-declarations dnl
+            -Wmissing-prototypes dnl
+            -Wstrict-prototypes dnl
+            -Wredundant-decls dnl
+            -Wno-unused-parameter dnl
+            -Wno-missing-field-initializers dnl
+            -Wdeclaration-after-statement dnl
+            -Wformat=2 dnl
+            -Wold-style-definition dnl
+            -Wcast-align dnl
+            -Wformat-nonliteral dnl
+            -Wformat-security dnl
+            -Wsign-compare dnl
+            -Wstrict-aliasing dnl
+            -Wshadow dnl
+            -Winline dnl
+            -Wpacked dnl
+            -Wmissing-format-attribute dnl
+            -Wmissing-noreturn dnl
+            -Winit-self dnl
+            -Wredundant-decls dnl
+            -Wmissing-include-dirs dnl
+            -Wunused-but-set-variable dnl
+            -Warray-bounds dnl
+            -Wimplicit-function-declaration dnl
+            -Wreturn-type dnl
+            -Wswitch-enum dnl
+            -Wswitch-default dnl
+            $4 dnl
+            $5 dnl
+            $6 dnl
+            $7 dnl
+        ],ax_warn_cflags_variable,[$ax_compiler_flags_test])
+    ])
+    AS_IF([test "$ax_enable_compile_warnings" = "error"],[
+        # "error" flags; -Werror has to be appended unconditionally because
+        # it's not possible to test for
+        #
+        # suggest-attribute=format is disabled because it gives too many false
+        # positives
+        AX_APPEND_FLAG([-Werror],ax_warn_cflags_variable)
+
+        AX_APPEND_COMPILE_FLAGS([ dnl
+            -Wno-suggest-attribute=format dnl
+        ],ax_warn_cflags_variable,[$ax_compiler_flags_test])
+    ])
+
+    # In the flags below, when disabling specific flags, always add *both*
+    # -Wno-foo and -Wno-error=foo. This fixes the situation where (for example)
+    # we enable -Werror, disable a flag, and a build bot passes CFLAGS=-Wall,
+    # which effectively turns that flag back on again as an error.
+    for flag in $ax_warn_cflags_variable; do
+        AS_CASE([$flag],
+                [-Wno-*=*],[],
+                [-Wno-*],[
+                    AX_APPEND_COMPILE_FLAGS([-Wno-error=$(AS_ECHO([$flag]) | $SED 's/^-Wno-//')],
+                                            ax_warn_cflags_variable,
+                                            [$ax_compiler_flags_test])
+                ])
+    done
+
+    AC_LANG_POP([C])
+
+    # Substitute the variables
+    AC_SUBST(ax_warn_cflags_variable)
+])dnl AX_COMPILER_FLAGS
+
+# ==============================================================================
+#  http://www.gnu.org/software/autoconf-archive/ax_compiler_flags_cxxflags.html
+# ==============================================================================
+#
+# SYNOPSIS
+#
+#   AX_COMPILER_FLAGS_CXXFLAGS([VARIABLE], [IS-RELEASE], [EXTRA-BASE-FLAGS], [EXTRA-YES-FLAGS])
+#
+# DESCRIPTION
+#
+#   Add warning flags for the C++ compiler to VARIABLE, which defaults to
+#   WARN_CXXFLAGS.  VARIABLE is AC_SUBST-ed by this macro, but must be
+#   manually added to the CXXFLAGS variable for each target in the code
+#   base.
+#
+#   This macro depends on the environment set up by AX_COMPILER_FLAGS.
+#   Specifically, it uses the value of $ax_enable_compile_warnings to decide
+#   which flags to enable.
+#
+# LICENSE
+#
+#   Copyright (c) 2015 David King <amigadave@amigadave.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 7
+
+AC_DEFUN([AX_COMPILER_FLAGS_CXXFLAGS],[
+    AC_REQUIRE([AC_PROG_SED])
+    AX_REQUIRE_DEFINED([AX_APPEND_COMPILE_FLAGS])
+    AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+    AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
+
+    # Variable names
+    m4_define(ax_warn_cxxflags_variable,
+              [m4_normalize(ifelse([$1],,[WARN_CXXFLAGS],[$1]))])
+
+    AC_LANG_PUSH([C++])
+
+    # Always pass -Werror=unknown-warning-option to get Clang to fail on bad
+    # flags, otherwise they are always appended to the warn_cxxflags variable,
+    # and Clang warns on them for every compilation unit.
+    # If this is passed to GCC, it will explode, so the flag must be enabled
+    # conditionally.
+    AX_CHECK_COMPILE_FLAG([-Werror=unknown-warning-option],[
+        ax_compiler_flags_test="-Werror=unknown-warning-option"
+    ],[
+        ax_compiler_flags_test=""
+    ])
+
+    # Base flags
+    AX_APPEND_COMPILE_FLAGS([ dnl
+        -fno-strict-aliasing dnl
+        $3 dnl
+    ],ax_warn_cxxflags_variable,[$ax_compiler_flags_test])
+
+    AS_IF([test "$ax_enable_compile_warnings" != "no"],[
+        # "yes" flags
+        AX_APPEND_COMPILE_FLAGS([ dnl
+            -Wall dnl
+            -Wextra dnl
+            -Wundef dnl
+            -Wwrite-strings dnl
+            -Wpointer-arith dnl
+            -Wmissing-declarations dnl
+            -Wredundant-decls dnl
+            -Wno-unused-parameter dnl
+            -Wno-missing-field-initializers dnl
+            -Wformat=2 dnl
+            -Wcast-align dnl
+            -Wformat-nonliteral dnl
+            -Wformat-security dnl
+            -Wsign-compare dnl
+            -Wstrict-aliasing dnl
+            -Wshadow dnl
+            -Winline dnl
+            -Wpacked dnl
+            -Wmissing-format-attribute dnl
+            -Wmissing-noreturn dnl
+            -Winit-self dnl
+            -Wredundant-decls dnl
+            -Wmissing-include-dirs dnl
+            -Wunused-but-set-variable dnl
+            -Warray-bounds dnl
+            -Wreturn-type dnl
+            -Wno-overloaded-virtual dnl
+            -Wswitch-enum dnl
+            -Wswitch-default dnl
+            $4 dnl
+            $5 dnl
+            $6 dnl
+            $7 dnl
+        ],ax_warn_cxxflags_variable,[$ax_compiler_flags_test])
+    ])
+    AS_IF([test "$ax_enable_compile_warnings" = "error"],[
+        # "error" flags; -Werror has to be appended unconditionally because
+        # it's not possible to test for
+        #
+        # suggest-attribute=format is disabled because it gives too many false
+        # positives
+        AX_APPEND_FLAG([-Werror],ax_warn_cxxflags_variable)
+
+        AX_APPEND_COMPILE_FLAGS([ dnl
+            -Wno-suggest-attribute=format dnl
+        ],ax_warn_cxxflags_variable,[$ax_compiler_flags_test])
+    ])
+
+    # In the flags below, when disabling specific flags, always add *both*
+    # -Wno-foo and -Wno-error=foo. This fixes the situation where (for example)
+    # we enable -Werror, disable a flag, and a build bot passes CXXFLAGS=-Wall,
+    # which effectively turns that flag back on again as an error.
+    for flag in $ax_warn_cxxflags_variable; do
+        AS_CASE([$flag],
+                [-Wno-*=*],[],
+                [-Wno-*],[
+                    AX_APPEND_COMPILE_FLAGS([-Wno-error=$(AS_ECHO([$flag]) | $SED 's/^-Wno-//')],
+                                            ax_warn_cxxflags_variable,
+                                            [$ax_compiler_flags_test])
+                ])
+    done
+
+    AC_LANG_POP([C++])
+
+    # Substitute the variables
+    AC_SUBST(ax_warn_cxxflags_variable)
+])dnl AX_COMPILER_FLAGS_CXXFLAGS
+
+# ===========================================================================
+#   http://www.gnu.org/software/autoconf-archive/ax_compiler_flags_gir.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_COMPILER_FLAGS_GIR([VARIABLE], [IS-RELEASE], [EXTRA-BASE-FLAGS], [EXTRA-YES-FLAGS])
+#
+# DESCRIPTION
+#
+#   Add warning flags for the g-ir-scanner (from GObject Introspection) to
+#   VARIABLE, which defaults to WARN_SCANNERFLAGS.  VARIABLE is AC_SUBST-ed
+#   by this macro, but must be manually added to the SCANNERFLAGS variable
+#   for each GIR target in the code base.
+#
+#   This macro depends on the environment set up by AX_COMPILER_FLAGS.
+#   Specifically, it uses the value of $ax_enable_compile_warnings to decide
+#   which flags to enable.
+#
+# LICENSE
+#
+#   Copyright (c) 2015 Philip Withnall <philip@tecnocode.co.uk>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 4
+
+AC_DEFUN([AX_COMPILER_FLAGS_GIR],[
+    AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+
+    # Variable names
+    m4_define(ax_warn_scannerflags_variable,
+              [m4_normalize(ifelse([$1],,[WARN_SCANNERFLAGS],[$1]))])
+
+    # Base flags
+    AX_APPEND_FLAG([$3],ax_warn_scannerflags_variable)
+
+    AS_IF([test "$ax_enable_compile_warnings" != "no"],[
+        # "yes" flags
+        AX_APPEND_FLAG([ dnl
+            --warn-all dnl
+            $4 dnl
+            $5 dnl
+            $6 dnl
+            $7 dnl
+        ],ax_warn_scannerflags_variable)
+    ])
+    AS_IF([test "$ax_enable_compile_warnings" = "error"],[
+        # "error" flags
+        AX_APPEND_FLAG([ dnl
+            --warn-error dnl
+        ],ax_warn_scannerflags_variable)
+    ])
+
+    # Substitute the variables
+    AC_SUBST(ax_warn_scannerflags_variable)
+])dnl AX_COMPILER_FLAGS
+
+# =============================================================================
+#  http://www.gnu.org/software/autoconf-archive/ax_compiler_flags_ldflags.html
+# =============================================================================
+#
+# SYNOPSIS
+#
+#   AX_COMPILER_FLAGS_LDFLAGS([VARIABLE], [IS-RELEASE], [EXTRA-BASE-FLAGS], [EXTRA-YES-FLAGS])
+#
+# DESCRIPTION
+#
+#   Add warning flags for the linker to VARIABLE, which defaults to
+#   WARN_LDFLAGS.  VARIABLE is AC_SUBST-ed by this macro, but must be
+#   manually added to the LDFLAGS variable for each target in the code base.
+#
+#   This macro depends on the environment set up by AX_COMPILER_FLAGS.
+#   Specifically, it uses the value of $ax_enable_compile_warnings to decide
+#   which flags to enable.
+#
+# LICENSE
+#
+#   Copyright (c) 2014, 2015 Philip Withnall <philip@tecnocode.co.uk>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved.  This file is offered as-is, without any
+#   warranty.
+
+#serial 5
+
+AC_DEFUN([AX_COMPILER_FLAGS_LDFLAGS],[
+    AX_REQUIRE_DEFINED([AX_APPEND_LINK_FLAGS])
+    AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
+    AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
+
+    # Variable names
+    m4_define(ax_warn_ldflags_variable,
+              [m4_normalize(ifelse([$1],,[WARN_LDFLAGS],[$1]))])
+
+    # Always pass -Werror=unknown-warning-option to get Clang to fail on bad
+    # flags, otherwise they are always appended to the warn_ldflags variable,
+    # and Clang warns on them for every compilation unit.
+    # If this is passed to GCC, it will explode, so the flag must be enabled
+    # conditionally.
+    AX_CHECK_COMPILE_FLAG([-Werror=unknown-warning-option],[
+        ax_compiler_flags_test="-Werror=unknown-warning-option"
+    ],[
+        ax_compiler_flags_test=""
+    ])
+
+    # Base flags
+    AX_APPEND_LINK_FLAGS([ dnl
+        -Wl,--no-as-needed dnl
+        $3 dnl
+    ],ax_warn_ldflags_variable,[$ax_compiler_flags_test])
+
+    AS_IF([test "$ax_enable_compile_warnings" != "no"],[
+        # "yes" flags
+        AX_APPEND_LINK_FLAGS([$4 $5 $6 $7],
+                                ax_warn_ldflags_variable,
+                                [$ax_compiler_flags_test])
+    ])
+    AS_IF([test "$ax_enable_compile_warnings" = "error"],[
+        # "error" flags; -Werror has to be appended unconditionally because
+        # it's not possible to test for
+        #
+        # suggest-attribute=format is disabled because it gives too many false
+        # positives
+        AX_APPEND_LINK_FLAGS([ dnl
+            -Wl,--fatal-warnings dnl
+        ],ax_warn_ldflags_variable,[$ax_compiler_flags_test])
+    ])
+
+    # Substitute the variables
+    AC_SUBST(ax_warn_ldflags_variable)
+])dnl AX_COMPILER_FLAGS
+
 # longlong.m4 serial 17
 dnl Copyright (C) 1999-2007, 2009-2015 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
diff --git a/configure b/configure
index d9adcfb..10f8d83 100755
--- a/configure
+++ b/configure
@@ -2,7 +2,7 @@
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.69 for ImageMagick 7.0.0-0.
 #
-# Report bugs to <http://www.imagemagick.org>.
+# Report bugs to <https://github.com/ImageMagick/ImageMagick/issues>.
 #
 #
 # Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
@@ -275,10 +275,10 @@
     $as_echo "$0: be upgraded to zsh 4.3.4 or later."
   else
     $as_echo "$0: Please tell bug-autoconf@gnu.org and
-$0: http://www.imagemagick.org about your system, including
-$0: any error possibly output before this message. Then
-$0: install a modern shell, or manually run the script
-$0: under such a shell if you do have one."
+$0: https://github.com/ImageMagick/ImageMagick/issues about
+$0: your system, including any error possibly output before
+$0: this message. Then install a modern shell, or manually
+$0: run the script under such a shell if you do have one."
   fi
   exit 1
 fi
@@ -592,8 +592,8 @@
 PACKAGE_TARNAME='ImageMagick'
 PACKAGE_VERSION='7.0.0-0'
 PACKAGE_STRING='ImageMagick 7.0.0-0'
-PACKAGE_BUGREPORT='http://www.imagemagick.org'
-PACKAGE_URL=''
+PACKAGE_BUGREPORT='https://github.com/ImageMagick/ImageMagick/issues'
+PACKAGE_URL='http://www.imagemagick.org'
 
 ac_unique_file="MagickCore/MagickCore.h"
 # Factoring default headers for most tests.
@@ -971,6 +971,10 @@
 GDI32_LIBS
 HAVE_LD_VERSION_SCRIPT_FALSE
 HAVE_LD_VERSION_SCRIPT_TRUE
+WARN_SCANNERFLAGS
+WARN_LDFLAGS
+WARN_CXXFLAGS
+WARN_CFLAGS
 PKG_CONFIG_LIBDIR
 PKG_CONFIG_PATH
 PKG_CONFIG
@@ -1147,6 +1151,8 @@
 with_gnu_ld
 with_dmalloc
 with_gcc_arch
+enable_compile_warnings
+enable_Werror
 enable_ld_version_script
 enable_bounds_checking
 enable_osx_universal_binary
@@ -1910,6 +1916,9 @@
                           do not reject slow dependency extractors
   --disable-dependency-tracking
                           speeds up one-time build
+  --enable-compile-warnings=[no/yes/error]
+                          Enable compiler warnings and errors
+  --disable-Werror        Unconditionally make all compiler warnings non-fatal
   --enable-ld-version-script
                           enable linker version script (default is enabled
                           when possible)
@@ -2099,7 +2108,8 @@
 Use these variables to override the choices made by `configure' or to help
 it to find libraries and programs with nonstandard names/locations.
 
-Report bugs to <http://www.imagemagick.org>.
+Report bugs to <https://github.com/ImageMagick/ImageMagick/issues>.
+ImageMagick home page: <http://www.imagemagick.org>.
 _ACEOF
 ac_status=$?
 fi
@@ -2321,9 +2331,9 @@
 $as_echo "$as_me: WARNING: $2:     section \"Present But Cannot Be Compiled\"" >&2;}
     { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $2: proceeding with the compiler's result" >&5
 $as_echo "$as_me: WARNING: $2: proceeding with the compiler's result" >&2;}
-( $as_echo "## ----------------------------------------- ##
-## Report this to http://www.imagemagick.org ##
-## ----------------------------------------- ##"
+( $as_echo "## ---------------------------------------------------------------- ##
+## Report this to https://github.com/ImageMagick/ImageMagick/issues ##
+## ---------------------------------------------------------------- ##"
      ) | sed "s/^/$as_me: WARNING:     /" >&2
     ;;
 esac
@@ -3189,9 +3199,9 @@
 $as_echo "$as_me: WARNING: $2:     section \"Present But Cannot Be Compiled\"" >&2;}
     { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $2: proceeding with the compiler's result" >&5
 $as_echo "$as_me: WARNING: $2: proceeding with the compiler's result" >&2;}
-( $as_echo "## ----------------------------------------- ##
-## Report this to http://www.imagemagick.org ##
-## ----------------------------------------- ##"
+( $as_echo "## ---------------------------------------------------------------- ##
+## Report this to https://github.com/ImageMagick/ImageMagick/issues ##
+## ---------------------------------------------------------------- ##"
      ) | sed "s/^/$as_me: WARNING:     /" >&2
     ;;
 esac
@@ -4241,125 +4251,9 @@
 
 
 # We'll loop over all known methods to create a tar archive until one works.
-_am_tools='gnutar plaintar pax cpio none'
+_am_tools='gnutar  pax cpio none'
 
-# The POSIX 1988 'ustar' format is defined with fixed-size fields.
-      # There is notably a 21 bits limit for the UID and the GID.  In fact,
-      # the 'pax' utility can hang on bigger UID/GID (see automake bug#8343
-      # and bug#13588).
-      am_max_uid=2097151 # 2^21 - 1
-      am_max_gid=$am_max_uid
-      # The $UID and $GID variables are not portable, so we need to resort
-      # to the POSIX-mandated id(1) utility.  Errors in the 'id' calls
-      # below are definitely unexpected, so allow the users to see them
-      # (that is, avoid stderr redirection).
-      am_uid=`id -u || echo unknown`
-      am_gid=`id -g || echo unknown`
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether UID '$am_uid' is supported by ustar format" >&5
-$as_echo_n "checking whether UID '$am_uid' is supported by ustar format... " >&6; }
-      if test $am_uid -le $am_max_uid; then
-         { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-      else
-         { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-         _am_tools=none
-      fi
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether GID '$am_gid' is supported by ustar format" >&5
-$as_echo_n "checking whether GID '$am_gid' is supported by ustar format... " >&6; }
-      if test $am_gid -le $am_max_gid; then
-         { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-      else
-        { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-        _am_tools=none
-      fi
-
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking how to create a ustar tar archive" >&5
-$as_echo_n "checking how to create a ustar tar archive... " >&6; }
-
-  # Go ahead even if we have the value already cached.  We do so because we
-  # need to set the values for the 'am__tar' and 'am__untar' variables.
-  _am_tools=${am_cv_prog_tar_ustar-$_am_tools}
-
-  for _am_tool in $_am_tools; do
-    case $_am_tool in
-    gnutar)
-      for _am_tar in tar gnutar gtar; do
-        { echo "$as_me:$LINENO: $_am_tar --version" >&5
-   ($_am_tar --version) >&5 2>&5
-   ac_status=$?
-   echo "$as_me:$LINENO: \$? = $ac_status" >&5
-   (exit $ac_status); } && break
-      done
-      am__tar="$_am_tar --format=ustar -chf - "'"$$tardir"'
-      am__tar_="$_am_tar --format=ustar -chf - "'"$tardir"'
-      am__untar="$_am_tar -xf -"
-      ;;
-    plaintar)
-      # Must skip GNU tar: if it does not support --format= it doesn't create
-      # ustar tarball either.
-      (tar --version) >/dev/null 2>&1 && continue
-      am__tar='tar chf - "$$tardir"'
-      am__tar_='tar chf - "$tardir"'
-      am__untar='tar xf -'
-      ;;
-    pax)
-      am__tar='pax -L -x ustar -w "$$tardir"'
-      am__tar_='pax -L -x ustar -w "$tardir"'
-      am__untar='pax -r'
-      ;;
-    cpio)
-      am__tar='find "$$tardir" -print | cpio -o -H ustar -L'
-      am__tar_='find "$tardir" -print | cpio -o -H ustar -L'
-      am__untar='cpio -i -H ustar -d'
-      ;;
-    none)
-      am__tar=false
-      am__tar_=false
-      am__untar=false
-      ;;
-    esac
-
-    # If the value was cached, stop now.  We just wanted to have am__tar
-    # and am__untar set.
-    test -n "${am_cv_prog_tar_ustar}" && break
-
-    # tar/untar a dummy directory, and stop if the command works.
-    rm -rf conftest.dir
-    mkdir conftest.dir
-    echo GrepMe > conftest.dir/file
-    { echo "$as_me:$LINENO: tardir=conftest.dir && eval $am__tar_ >conftest.tar" >&5
-   (tardir=conftest.dir && eval $am__tar_ >conftest.tar) >&5 2>&5
-   ac_status=$?
-   echo "$as_me:$LINENO: \$? = $ac_status" >&5
-   (exit $ac_status); }
-    rm -rf conftest.dir
-    if test -s conftest.tar; then
-      { echo "$as_me:$LINENO: $am__untar <conftest.tar" >&5
-   ($am__untar <conftest.tar) >&5 2>&5
-   ac_status=$?
-   echo "$as_me:$LINENO: \$? = $ac_status" >&5
-   (exit $ac_status); }
-      { echo "$as_me:$LINENO: cat conftest.dir/file" >&5
-   (cat conftest.dir/file) >&5 2>&5
-   ac_status=$?
-   echo "$as_me:$LINENO: \$? = $ac_status" >&5
-   (exit $ac_status); }
-      grep GrepMe conftest.dir/file >/dev/null 2>&1 && break
-    fi
-  done
-  rm -rf conftest.dir
-
-  if ${am_cv_prog_tar_ustar+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  am_cv_prog_tar_ustar=$_am_tool
-fi
-
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_prog_tar_ustar" >&5
-$as_echo "$am_cv_prog_tar_ustar" >&6; }
+am__tar='$${TAR-tar} chof - "$$tardir"' am__untar='$${TAR-tar} xf -'
 
 
 
@@ -4513,7 +4407,7 @@
 
 MAGICK_VERSION=7.0.0-0
 
-MAGICK_GIT_REVISION=17653:80353a3:20160209
+MAGICK_GIT_REVISION=17656:f4f5483:20160209
 
 
 # Substitute library versioning
@@ -9307,7 +9201,7 @@
 
 fi
 if test -n "$PKG_CONFIG"; then
-	_pkg_min_version=0.9.0
+	_pkg_min_version=0.20
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking pkg-config is at least version $_pkg_min_version" >&5
 $as_echo_n "checking pkg-config is at least version $_pkg_min_version... " >&6; }
 	if $PKG_CONFIG --atleast-pkgconfig-version $_pkg_min_version; then
@@ -9415,6 +9309,1356 @@
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_c_compiler_vendor" >&5
 $as_echo "$ax_cv_c_compiler_vendor" >&6; }
 
+
+
+    # C support is enabled by default.
+
+
+    # Only enable C++ support if AC_PROG_CXX is called. The redefinition of
+    # AC_PROG_CXX is so that a fatal error is emitted if this macro is called
+    # before AC_PROG_CXX, which would otherwise cause no C++ warnings to be
+    # checked.
+
+
+
+
+
+    # Default value for IS-RELEASE is $ax_is_release
+    ax_compiler_flags_is_release=$ax_is_release
+
+    # Check whether --enable-compile-warnings was given.
+if test "${enable_compile_warnings+set}" = set; then :
+  enableval=$enable_compile_warnings;
+else
+  if test "$ax_compiler_flags_is_release" = "yes"; then :
+  enable_compile_warnings="yes"
+else
+  enable_compile_warnings="error"
+fi
+fi
+
+    # Check whether --enable-Werror was given.
+if test "${enable_Werror+set}" = set; then :
+  enableval=$enable_Werror;
+else
+  enable_Werror=maybe
+fi
+
+
+    # Return the user's chosen warning level
+    if test "$enable_Werror" = "no" -a \
+                "$enable_compile_warnings" = "error"; then :
+
+        enable_compile_warnings="yes"
+
+fi
+
+    ax_enable_compile_warnings=$enable_compile_warnings
+
+
+
+
+
+
+
+
+
+
+    # Variable names
+
+
+    ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+    # Always pass -Werror=unknown-warning-option to get Clang to fail on bad
+    # flags, otherwise they are always appended to the warn_cflags variable, and
+    # Clang warns on them for every compilation unit.
+    # If this is passed to GCC, it will explode, so the flag must be enabled
+    # conditionally.
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts -Werror=unknown-warning-option" >&5
+$as_echo_n "checking whether C compiler accepts -Werror=unknown-warning-option... " >&6; }
+if ${ax_cv_check_cflags___Werror_unknown_warning_option+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CFLAGS
+  CFLAGS="$CFLAGS  -Werror=unknown-warning-option"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  ax_cv_check_cflags___Werror_unknown_warning_option=yes
+else
+  ax_cv_check_cflags___Werror_unknown_warning_option=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS=$ax_check_save_flags
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_check_cflags___Werror_unknown_warning_option" >&5
+$as_echo "$ax_cv_check_cflags___Werror_unknown_warning_option" >&6; }
+if test "x$ax_cv_check_cflags___Werror_unknown_warning_option" = xyes; then :
+
+        ax_compiler_flags_test="-Werror=unknown-warning-option"
+
+else
+
+        ax_compiler_flags_test=""
+
+fi
+
+
+    # Base flags
+
+
+
+
+for flag in          -fno-strict-aliasing              ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts $flag" >&5
+$as_echo_n "checking whether C compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CFLAGS
+  CFLAGS="$CFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CFLAGS+:} false; then :
+
+  case " $WARN_CFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS already contains \$flag"; } >&5
+  (: WARN_CFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+    if test "$ax_enable_compile_warnings" != "no"; then :
+
+        # "yes" flags
+
+
+
+
+for flag in              -Wall             -Wextra             -Wundef             -Wnested-externs             -Wwrite-strings             -Wpointer-arith             -Wmissing-declarations             -Wmissing-prototypes             -Wstrict-prototypes             -Wredundant-decls             -Wno-unused-parameter             -Wno-missing-field-initializers             -Wdeclaration-after-statement             -Wformat=2             -Wold-style-definition             -Wcast-align             -Wformat-nonliteral             -Wformat-security             -Wsign-compare             -Wstrict-aliasing             -Wshadow             -Winline             -Wpacked             -Wmissing-format-attribute             -Wmissing-noreturn             -Winit-self             -Wredundant-decls             -Wmissing-include-dirs             -Wunused-but-set-variable             -Warray-bounds             -Wimplicit-function-declaration             -Wreturn-type             -Wswitch-enum             -Wswitch-default                                                                ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts $flag" >&5
+$as_echo_n "checking whether C compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CFLAGS
+  CFLAGS="$CFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CFLAGS+:} false; then :
+
+  case " $WARN_CFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS already contains \$flag"; } >&5
+  (: WARN_CFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+fi
+    if test "$ax_enable_compile_warnings" = "error"; then :
+
+        # "error" flags; -Werror has to be appended unconditionally because
+        # it's not possible to test for
+        #
+        # suggest-attribute=format is disabled because it gives too many false
+        # positives
+
+if ${WARN_CFLAGS+:} false; then :
+
+  case " $WARN_CFLAGS " in #(
+  *" -Werror "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS already contains -Werror"; } >&5
+  (: WARN_CFLAGS already contains -Werror) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CFLAGS " -Werror"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CFLAGS=-Werror
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+
+
+
+
+
+for flag in              -Wno-suggest-attribute=format         ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts $flag" >&5
+$as_echo_n "checking whether C compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CFLAGS
+  CFLAGS="$CFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CFLAGS+:} false; then :
+
+  case " $WARN_CFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS already contains \$flag"; } >&5
+  (: WARN_CFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+fi
+
+    # In the flags below, when disabling specific flags, always add *both*
+    # -Wno-foo and -Wno-error=foo. This fixes the situation where (for example)
+    # we enable -Werror, disable a flag, and a build bot passes CFLAGS=-Wall,
+    # which effectively turns that flag back on again as an error.
+    for flag in $WARN_CFLAGS; do
+        case $flag in #(
+  -Wno-*=*) :
+     ;; #(
+  -Wno-*) :
+
+
+
+
+
+for flag in -Wno-error=$($as_echo $flag | $SED 's/^-Wno-//'); do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts $flag" >&5
+$as_echo_n "checking whether C compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CFLAGS
+  CFLAGS="$CFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CFLAGS+:} false; then :
+
+  case " $WARN_CFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS already contains \$flag"; } >&5
+  (: WARN_CFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CFLAGS=\"\$WARN_CFLAGS\""; } >&5
+  (: WARN_CFLAGS="$WARN_CFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+                 ;; #(
+  *) :
+     ;;
+esac
+    done
+
+    ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+    # Substitute the variables
+
+
+
+
+
+
+
+
+
+
+
+    # Variable names
+
+
+    ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+
+    # Always pass -Werror=unknown-warning-option to get Clang to fail on bad
+    # flags, otherwise they are always appended to the warn_cxxflags variable,
+    # and Clang warns on them for every compilation unit.
+    # If this is passed to GCC, it will explode, so the flag must be enabled
+    # conditionally.
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C++ compiler accepts -Werror=unknown-warning-option" >&5
+$as_echo_n "checking whether C++ compiler accepts -Werror=unknown-warning-option... " >&6; }
+if ${ax_cv_check_cxxflags___Werror_unknown_warning_option+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CXXFLAGS
+  CXXFLAGS="$CXXFLAGS  -Werror=unknown-warning-option"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  ax_cv_check_cxxflags___Werror_unknown_warning_option=yes
+else
+  ax_cv_check_cxxflags___Werror_unknown_warning_option=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CXXFLAGS=$ax_check_save_flags
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_check_cxxflags___Werror_unknown_warning_option" >&5
+$as_echo "$ax_cv_check_cxxflags___Werror_unknown_warning_option" >&6; }
+if test "x$ax_cv_check_cxxflags___Werror_unknown_warning_option" = xyes; then :
+
+        ax_compiler_flags_test="-Werror=unknown-warning-option"
+
+else
+
+        ax_compiler_flags_test=""
+
+fi
+
+
+    # Base flags
+
+
+
+
+for flag in          -fno-strict-aliasing              ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cxxflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C++ compiler accepts $flag" >&5
+$as_echo_n "checking whether C++ compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CXXFLAGS
+  CXXFLAGS="$CXXFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CXXFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CXXFLAGS+:} false; then :
+
+  case " $WARN_CXXFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS already contains \$flag"; } >&5
+  (: WARN_CXXFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CXXFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CXXFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+    if test "$ax_enable_compile_warnings" != "no"; then :
+
+        # "yes" flags
+
+
+
+
+for flag in              -Wall             -Wextra             -Wundef             -Wwrite-strings             -Wpointer-arith             -Wmissing-declarations             -Wredundant-decls             -Wno-unused-parameter             -Wno-missing-field-initializers             -Wformat=2             -Wcast-align             -Wformat-nonliteral             -Wformat-security             -Wsign-compare             -Wstrict-aliasing             -Wshadow             -Winline             -Wpacked             -Wmissing-format-attribute             -Wmissing-noreturn             -Winit-self             -Wredundant-decls             -Wmissing-include-dirs             -Wunused-but-set-variable             -Warray-bounds             -Wreturn-type             -Wno-overloaded-virtual             -Wswitch-enum             -Wswitch-default                                                                ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cxxflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C++ compiler accepts $flag" >&5
+$as_echo_n "checking whether C++ compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CXXFLAGS
+  CXXFLAGS="$CXXFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CXXFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CXXFLAGS+:} false; then :
+
+  case " $WARN_CXXFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS already contains \$flag"; } >&5
+  (: WARN_CXXFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CXXFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CXXFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+fi
+    if test "$ax_enable_compile_warnings" = "error"; then :
+
+        # "error" flags; -Werror has to be appended unconditionally because
+        # it's not possible to test for
+        #
+        # suggest-attribute=format is disabled because it gives too many false
+        # positives
+
+if ${WARN_CXXFLAGS+:} false; then :
+
+  case " $WARN_CXXFLAGS " in #(
+  *" -Werror "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS already contains -Werror"; } >&5
+  (: WARN_CXXFLAGS already contains -Werror) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CXXFLAGS " -Werror"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CXXFLAGS=-Werror
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+
+
+
+
+
+for flag in              -Wno-suggest-attribute=format         ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cxxflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C++ compiler accepts $flag" >&5
+$as_echo_n "checking whether C++ compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CXXFLAGS
+  CXXFLAGS="$CXXFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CXXFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CXXFLAGS+:} false; then :
+
+  case " $WARN_CXXFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS already contains \$flag"; } >&5
+  (: WARN_CXXFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CXXFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CXXFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+fi
+
+    # In the flags below, when disabling specific flags, always add *both*
+    # -Wno-foo and -Wno-error=foo. This fixes the situation where (for example)
+    # we enable -Werror, disable a flag, and a build bot passes CXXFLAGS=-Wall,
+    # which effectively turns that flag back on again as an error.
+    for flag in $WARN_CXXFLAGS; do
+        case $flag in #(
+  -Wno-*=*) :
+     ;; #(
+  -Wno-*) :
+
+
+
+
+
+for flag in -Wno-error=$($as_echo $flag | $SED 's/^-Wno-//'); do
+  as_CACHEVAR=`$as_echo "ax_cv_check_cxxflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C++ compiler accepts $flag" >&5
+$as_echo_n "checking whether C++ compiler accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CXXFLAGS
+  CXXFLAGS="$CXXFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CXXFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_CXXFLAGS+:} false; then :
+
+  case " $WARN_CXXFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS already contains \$flag"; } >&5
+  (: WARN_CXXFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_CXXFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_CXXFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_CXXFLAGS=\"\$WARN_CXXFLAGS\""; } >&5
+  (: WARN_CXXFLAGS="$WARN_CXXFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+                 ;; #(
+  *) :
+     ;;
+esac
+    done
+
+    ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+    # Substitute the variables
+
+
+
+
+
+
+
+
+
+
+    # Variable names
+
+
+    # Always pass -Werror=unknown-warning-option to get Clang to fail on bad
+    # flags, otherwise they are always appended to the warn_ldflags variable,
+    # and Clang warns on them for every compilation unit.
+    # If this is passed to GCC, it will explode, so the flag must be enabled
+    # conditionally.
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts -Werror=unknown-warning-option" >&5
+$as_echo_n "checking whether C compiler accepts -Werror=unknown-warning-option... " >&6; }
+if ${ax_cv_check_cflags___Werror_unknown_warning_option+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$CFLAGS
+  CFLAGS="$CFLAGS  -Werror=unknown-warning-option"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  ax_cv_check_cflags___Werror_unknown_warning_option=yes
+else
+  ax_cv_check_cflags___Werror_unknown_warning_option=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+  CFLAGS=$ax_check_save_flags
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_check_cflags___Werror_unknown_warning_option" >&5
+$as_echo "$ax_cv_check_cflags___Werror_unknown_warning_option" >&6; }
+if test "x$ax_cv_check_cflags___Werror_unknown_warning_option" = xyes; then :
+
+        ax_compiler_flags_test="-Werror=unknown-warning-option"
+
+else
+
+        ax_compiler_flags_test=""
+
+fi
+
+
+    # Base flags
+
+
+
+
+for flag in          -Wl,--no-as-needed              ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_ldflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker accepts $flag" >&5
+$as_echo_n "checking whether the linker accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$LDFLAGS
+  LDFLAGS="$LDFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+  LDFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_LDFLAGS+:} false; then :
+
+  case " $WARN_LDFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS already contains \$flag"; } >&5
+  (: WARN_LDFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_LDFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS=\"\$WARN_LDFLAGS\""; } >&5
+  (: WARN_LDFLAGS="$WARN_LDFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_LDFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS=\"\$WARN_LDFLAGS\""; } >&5
+  (: WARN_LDFLAGS="$WARN_LDFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+    if test "$ax_enable_compile_warnings" != "no"; then :
+
+        # "yes" flags
+
+
+
+
+for flag in       ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_ldflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker accepts $flag" >&5
+$as_echo_n "checking whether the linker accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$LDFLAGS
+  LDFLAGS="$LDFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+  LDFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_LDFLAGS+:} false; then :
+
+  case " $WARN_LDFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS already contains \$flag"; } >&5
+  (: WARN_LDFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_LDFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS=\"\$WARN_LDFLAGS\""; } >&5
+  (: WARN_LDFLAGS="$WARN_LDFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_LDFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS=\"\$WARN_LDFLAGS\""; } >&5
+  (: WARN_LDFLAGS="$WARN_LDFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+fi
+    if test "$ax_enable_compile_warnings" = "error"; then :
+
+        # "error" flags; -Werror has to be appended unconditionally because
+        # it's not possible to test for
+        #
+        # suggest-attribute=format is disabled because it gives too many false
+        # positives
+
+
+
+
+for flag in              -Wl,--fatal-warnings         ; do
+  as_CACHEVAR=`$as_echo "ax_cv_check_ldflags_$ax_compiler_flags_test_$flag" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker accepts $flag" >&5
+$as_echo_n "checking whether the linker accepts $flag... " >&6; }
+if eval \${$as_CACHEVAR+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+
+  ax_check_save_flags=$LDFLAGS
+  LDFLAGS="$LDFLAGS $ax_compiler_flags_test $flag"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$as_CACHEVAR=yes"
+else
+  eval "$as_CACHEVAR=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+  LDFLAGS=$ax_check_save_flags
+fi
+eval ac_res=\$$as_CACHEVAR
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_CACHEVAR"\" = x"yes"; then :
+
+if ${WARN_LDFLAGS+:} false; then :
+
+  case " $WARN_LDFLAGS " in #(
+  *" $flag "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS already contains \$flag"; } >&5
+  (: WARN_LDFLAGS already contains $flag) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_LDFLAGS " $flag"
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS=\"\$WARN_LDFLAGS\""; } >&5
+  (: WARN_LDFLAGS="$WARN_LDFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_LDFLAGS=$flag
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_LDFLAGS=\"\$WARN_LDFLAGS\""; } >&5
+  (: WARN_LDFLAGS="$WARN_LDFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+else
+  :
+fi
+
+done
+
+
+fi
+
+    # Substitute the variables
+
+
+
+
+
+
+    # Variable names
+
+
+    # Base flags
+
+if ${WARN_SCANNERFLAGS+:} false; then :
+
+  case " $WARN_SCANNERFLAGS " in #(
+  *"  "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS already contains "; } >&5
+  (: WARN_SCANNERFLAGS already contains ) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_SCANNERFLAGS " "
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS=\"\$WARN_SCANNERFLAGS\""; } >&5
+  (: WARN_SCANNERFLAGS="$WARN_SCANNERFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_SCANNERFLAGS=
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS=\"\$WARN_SCANNERFLAGS\""; } >&5
+  (: WARN_SCANNERFLAGS="$WARN_SCANNERFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+
+    if test "$ax_enable_compile_warnings" != "no"; then :
+
+        # "yes" flags
+
+if ${WARN_SCANNERFLAGS+:} false; then :
+
+  case " $WARN_SCANNERFLAGS " in #(
+  *"              --warn-all                                                              "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS already contains              --warn-all                                                             "; } >&5
+  (: WARN_SCANNERFLAGS already contains              --warn-all                                                             ) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_SCANNERFLAGS "              --warn-all                                                             "
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS=\"\$WARN_SCANNERFLAGS\""; } >&5
+  (: WARN_SCANNERFLAGS="$WARN_SCANNERFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_SCANNERFLAGS=             --warn-all
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS=\"\$WARN_SCANNERFLAGS\""; } >&5
+  (: WARN_SCANNERFLAGS="$WARN_SCANNERFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+
+fi
+    if test "$ax_enable_compile_warnings" = "error"; then :
+
+        # "error" flags
+
+if ${WARN_SCANNERFLAGS+:} false; then :
+
+  case " $WARN_SCANNERFLAGS " in #(
+  *"              --warn-error          "*) :
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS already contains              --warn-error         "; } >&5
+  (: WARN_SCANNERFLAGS already contains              --warn-error         ) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; } ;; #(
+  *) :
+
+     as_fn_append WARN_SCANNERFLAGS "              --warn-error         "
+     { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS=\"\$WARN_SCANNERFLAGS\""; } >&5
+  (: WARN_SCANNERFLAGS="$WARN_SCANNERFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+     ;;
+esac
+
+else
+
+  WARN_SCANNERFLAGS=             --warn-error
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: : WARN_SCANNERFLAGS=\"\$WARN_SCANNERFLAGS\""; } >&5
+  (: WARN_SCANNERFLAGS="$WARN_SCANNERFLAGS") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+
+fi
+
+
+fi
+
+    # Substitute the variables
+
+
+
 # The AX_CFLAGS_WARN_ALL macro doesn't currently work for sunpro
 # compiler.
 if test "$ax_cv_c_compiler_vendor" != "sun"; then
@@ -14393,7 +15637,6 @@
 
 
 
-
 func_stripname_cnf ()
 {
   case $2 in
@@ -37306,7 +38549,8 @@
 Configuration commands:
 $config_commands
 
-Report bugs to <http://www.imagemagick.org>."
+Report bugs to <https://github.com/ImageMagick/ImageMagick/issues>.
+ImageMagick home page: <http://www.imagemagick.org>."
 
 _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
diff --git a/configure.ac b/configure.ac
index bdf92af..ce5d9c7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -36,7 +36,11 @@
 # ==============================================================================
 # Initalize Automake
 # ==============================================================================
-AC_INIT([ImageMagick],[magick_version],[http://www.imagemagick.org],[magick_tar_name])
+AC_INIT([ImageMagick],
+        [magick_version],
+        [https://github.com/ImageMagick/ImageMagick/issues],
+        [magick_tar_name],
+        [http://www.imagemagick.org])
 AC_CONFIG_SRCDIR([MagickCore/MagickCore.h])
 AC_CONFIG_AUX_DIR([config])
 AC_REQUIRE_AUX_FILE([tap-driver.sh])
@@ -45,8 +49,8 @@
 AX_PREFIX_CONFIG_H([MagickCore/magick-baseconfig.h],[MagickCore])
 AC_CANONICAL_SYSTEM
 AC_CANONICAL_TARGET
-AM_INIT_AUTOMAKE([1.12 nostdinc color-tests foreign parallel-tests silent-rules subdir-objects dist-bzip2 dist-lzip dist-xz dist-zip tar-ustar])
-m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
+AM_INIT_AUTOMAKE([foreign color-tests -Wall -Wno-portability subdir-objects])
+AM_SILENT_RULES([yes])
 
 #
 # Save initial user-tunable values
@@ -294,7 +298,7 @@
 AM_WITH_DMALLOC
 AX_C___ATTRIBUTE__
 AX_GCC_ARCHFLAG([yes])
-PKG_PROG_PKG_CONFIG
+PKG_PROG_PKG_CONFIG([0.20])
 AC_CANONICAL_BUILD
 AC_CANONICAL_HOST
 
@@ -302,6 +306,7 @@
 AC_CHECK_SIZEOF([size_t])
 
 AX_COMPILER_VENDOR
+AX_COMPILER_FLAGS
 # The AX_CFLAGS_WARN_ALL macro doesn't currently work for sunpro
 # compiler.
 if test "$ax_cv_c_compiler_vendor" != "sun"; then