This patch aims to match the changes introduced
in gcc by https://gcc.gnu.org/ml/gcc-cvs/2018-04/msg00534.html.
The -mibt feature flag is being removed, and the -fcf-protection
option now also defines a CET macro and causes errors when used
on non-X86 targets, while X86 targets no longer check for -mibt
and -mshstk to determine if -fcf-protection is supported. -mshstk
is now used only to determine availability of shadow stack intrinsics.
Comes with an LLVM patch (D46882).
Patch by mike.dvoretsky
Differential Revision: https://reviews.llvm.org/D46881
llvm-svn: 332704
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 05e5196e..849e3ba 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -2829,6 +2829,17 @@
}
}
+ // Add the __CET__ macro if a CFProtection option is set.
+ if (const Arg *A = Args.getLastArg(OPT_fcf_protection_EQ)) {
+ StringRef Name = A->getValue();
+ if (Name == "branch")
+ Opts.addMacroDef("__CET__=1");
+ else if (Name == "return")
+ Opts.addMacroDef("__CET__=2");
+ else if (Name == "full")
+ Opts.addMacroDef("__CET__=3");
+ }
+
// Add macros from the command line.
for (const auto *A : Args.filtered(OPT_D, OPT_U)) {
if (A->getOption().matches(OPT_D))