bpo-30104: configure now detects when cc is clang (#1233)
Detect when the "cc" compiler (and the $CC variable) is the Clang
compiler. The test is needed to add the -fno-strict-aliasing option
on FreeBSD where cc is clang.
diff --git a/configure b/configure
index 40e64ad..1c90d31 100755
--- a/configure
+++ b/configure
@@ -6812,19 +6812,32 @@
WRAP="-fwrapv"
fi
- # Clang also needs -fwrapv
case $CC in
*clang*)
- WRAP="-fwrapv"
- # bpo-30104: Python/dtoa.c requires to be build with
- # -fno-strict-aliasing to fix compiler issue on the
- # double/ULong[2] union using clang 4.0 and optimization level
- # -O2 or higher
- # https://bugs.llvm.org//show_bug.cgi?id=31928
- ALIASING="-fno-strict-aliasing"
+ cc_is_clang=1
;;
+ *)
+ if $CC --version 2>&1 | grep -q clang
+ then
+ cc_is_clang=1
+ else
+ cc_is_clang=
+ fi
esac
+ if test -n "${cc_is_clang}"
+ then
+ # Clang also needs -fwrapv
+ WRAP="-fwrapv"
+
+ # bpo-30104: Python/dtoa.c requires to be build with
+ # -fno-strict-aliasing to fix compiler issue on the
+ # double/ULong[2] union using clang 4.0 and optimization level
+ # -O2 or higher
+ # https://bugs.llvm.org//show_bug.cgi?id=31928
+ ALIASING="-fno-strict-aliasing"
+ fi
+
case $ac_cv_prog_cc_g in
yes)
if test "$Py_DEBUG" = 'true' ; then