Provide a -no-pedantic to cancel out -pedantic.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158416 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index 48f2b1a..73f5fbb 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -831,6 +831,7 @@
 def no_cpp_precomp : Flag<"-no-cpp-precomp">, Group<clang_ignored_f_Group>;
 def no_integrated_as : Flag<"-no-integrated-as">, Flags<[DriverOption]>;
 def no_integrated_cpp : Flag<"-no-integrated-cpp">, Flags<[DriverOption]>;
+def no_pedantic : Flag<"-no-pedantic">, Group<pedantic_Group>;
 def no__dead__strip__inits__and__terms : Flag<"-no_dead_strip_inits_and_terms">;
 def nobuiltininc : Flag<"-nobuiltininc">, Flags<[CC1Option]>,
   HelpText<"Disable builtin #include directories">;
@@ -1033,6 +1034,7 @@
 def _machine : Separate<"--machine">, Alias<m_Joined>;
 def _no_integrated_cpp : Flag<"--no-integrated-cpp">, Alias<no_integrated_cpp>;
 def _no_line_commands : Flag<"--no-line-commands">, Alias<P>;
+def _no_pedantic : Flag<"--no-pedantic">, Alias<no_pedantic>;
 def _no_standard_includes : Flag<"--no-standard-includes">, Alias<nostdinc>;
 def _no_standard_libraries : Flag<"--no-standard-libraries">, Alias<nostdlib>;
 def _no_undefined : Flag<"--no-undefined">, Flags<[LinkerInput]>;
diff --git a/lib/Driver/Tools.cpp b/lib/Driver/Tools.cpp
index e84c72f..dec9dba 100644
--- a/lib/Driver/Tools.cpp
+++ b/lib/Driver/Tools.cpp
@@ -2034,7 +2034,8 @@
   }
 
   Args.AddAllArgs(CmdArgs, options::OPT_W_Group);
-  Args.AddLastArg(CmdArgs, options::OPT_pedantic);
+  if (Args.hasFlag(options::OPT_pedantic, options::OPT_no_pedantic, false))
+    CmdArgs.push_back("-pedantic");
   Args.AddLastArg(CmdArgs, options::OPT_pedantic_errors);
   Args.AddLastArg(CmdArgs, options::OPT_w);
 
diff --git a/test/Driver/warning-options.cpp b/test/Driver/warning-options.cpp
index ce434ab..02b3e1c 100644
--- a/test/Driver/warning-options.cpp
+++ b/test/Driver/warning-options.cpp
@@ -8,3 +8,8 @@
 // CHECK: unknown warning option '-Wmonkey'
 // CHECK: unknown warning option '-Wno-monkey'
 // CHECK: unknown warning option '-Wno-unused-command-line-arguments'; did you mean '-Wno-unused-command-line-argument'?
+
+// RUN: %clang -### -pedantic -no-pedantic %s 2>&1 | FileCheck -check-prefix=NO_PEDANTIC %s
+// NO_PEDANTIC-NOT: -pedantic
+// RUN: %clang -### -pedantic -pedantic -no-pedantic -pedantic %s 2>&1 | FileCheck -check-prefix=PEDANTIC %s
+// PEDANTIC: -pedantic