clang-cl: Disable TBAA by default for MSVC compatibility
MSVC doesn't have an option to enable TBAA, so make -fstrict-aliasing
and -fno-strict-aliasing available in clang-cl.
llvm-svn: 205924
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index e65b6e1..2870283 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2508,8 +2508,11 @@
// enabled. This alias option is being used to simplify the hasFlag logic.
OptSpecifier StrictAliasingAliasOption = OFastEnabled ? options::OPT_Ofast :
options::OPT_fstrict_aliasing;
+ // We turn strict aliasing off by default if we're in CL mode, since MSVC
+ // doesn't do any TBAA.
+ bool TBAAOnByDefault = !getToolChain().getDriver().IsCLMode();
if (!Args.hasFlag(options::OPT_fstrict_aliasing, StrictAliasingAliasOption,
- options::OPT_fno_strict_aliasing, true))
+ options::OPT_fno_strict_aliasing, TBAAOnByDefault))
CmdArgs.push_back("-relaxed-aliasing");
if (!Args.hasFlag(options::OPT_fstruct_path_tbaa,
options::OPT_fno_struct_path_tbaa))