[Driver] Render target options (e.g. -fuse-init-array) for -fembed-bitcode

Modern ELF platforms use -fuse-init-array to emit .init_array instead of
.ctors .  ld.bfd and gold --ctors-in-init-array merge .init_array and
.ctors into .init_array but lld doesn't do that.

If crtbegin*.o crtend*.o don't provide .ctors/.dtors, such .ctors in
user object files can lead to crash (see PR42002. The first and the last
elements in .ctors/.dtors are ignored - they are traditionally provided
by crtbegin*.o crtend*.o).

Call addClangTargetOptions() to ensure -fuse-init-array is rendered on
modern ELF platforms. On Hexagon, this renders -target-feature
+reserved-r19 for -ffixed-r19.

Reviewed By: compnerd

Differential Revision: https://reviews.llvm.org/D62509

llvm-svn: 362052

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 3009bc8d292..650f73d36f2 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -3666,6 +3666,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     // Disable all llvm IR level optimizations.
     CmdArgs.push_back("-disable-llvm-passes");
 
+    // Render target options such as -fuse-init-array on modern ELF platforms.
+    TC.addClangTargetOptions(Args, CmdArgs, JA.getOffloadingDeviceKind());
+
     // reject options that shouldn't be supported in bitcode
     // also reject kernel/kext
     static const constexpr unsigned kBitcodeOptionBlacklist[] = {