[clang] 33ba8bd - [Windows SEH]: Fix -O2 crash for Windows -EHa

[Ten Tzen via cfe-commits]

Author: Ten Tzen
Date: 2021-06-04T14:07:44-07:00
New Revision: 33ba8bd2c942062731a17e1b864b5953e3d79f1a

URL: https://github.com/llvm/llvm-project/commit/33ba8bd2c942062731a17e1b864b5953e3d79f1a
DIFF: https://github.com/llvm/llvm-project/commit/33ba8bd2c942062731a17e1b864b5953e3d79f1a.diff

LOG: [Windows SEH]: Fix -O2 crash for Windows -EHa

This patch fixes a Windows -EHa crash induced by previous commit 797ad701522988e212495285dade8efac41a24d4.
The crash was caused by "LifetimeMarker" scope (with option -O2) that should not be considered as SEH Scope.

This change also turns off -fasync-exceptions by default under -EHa option for now.

Differential Revision: https://reviews.llvm.org/D103664#2799944

Added: 
    

Modified: 
    clang/lib/CodeGen/CGCleanup.cpp
    clang/lib/Driver/ToolChains/Clang.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGCleanup.cpp b/clang/lib/CodeGen/CGCleanup.cpp
index b439204cf047..b9364fcd2231 100644
--- a/clang/lib/CodeGen/CGCleanup.cpp
+++ b/clang/lib/CodeGen/CGCleanup.cpp
@@ -195,7 +195,7 @@ void *EHScopeStack::pushCleanup(CleanupKind Kind, size_t Size) {
     Scope->setLifetimeMarker();
 
   // With Windows -EHa, Invoke llvm.seh.scope.begin() for EHCleanup
-  if (CGF->getLangOpts().EHAsynch && IsEHCleanup &&
+  if (CGF->getLangOpts().EHAsynch && IsEHCleanup && !IsLifetimeMarker &&
       CGF->getTarget().getCXXABI().isMicrosoft())
     CGF->EmitSehCppScopeBegin();
 

diff  --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index ee40df35b850..a0e1208fd709 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -7151,8 +7151,6 @@ void Clang::AddClangCLArgs(const ArgList &Args, types::ID InputType,
     if (types::isCXX(InputType))
       CmdArgs.push_back("-fcxx-exceptions");
     CmdArgs.push_back("-fexceptions");
-    if (EH.Asynch)
-      CmdArgs.push_back("-fasync-exceptions");
   }
   if (types::isCXX(InputType) && EH.Synch && EH.NoUnwindC)
     CmdArgs.push_back("-fexternc-nounwind");