Fix a mangling failure on clang-cl C++17

MethodVFTableLocations in MigrosoftVTableContext contains canonicalized
decl. But, it's sometimes asked to lookup for non-canonicalized decl,
and that causes assertion failure, and compilation failure.

Fixes PR37481.

Patch by Taiju Tsuiki!

Differential Revision: https://reviews.llvm.org/D46929

llvm-svn: 332639

1 files changed, 5 insertions, 0 deletions

diff --git a/clang/lib/AST/VTableBuilder.cpp b/clang/lib/AST/VTableBuilder.cpp
index 9d7c9441085..0a3da024f14 100644
--- a/clang/lib/AST/VTableBuilder.cpp
+++ b/clang/lib/AST/VTableBuilder.cpp
@@ -2223,6 +2223,7 @@ ItaniumVTableContext::ItaniumVTableContext(ASTContext &Context)
 ItaniumVTableContext::~ItaniumVTableContext() {}
 
 uint64_t ItaniumVTableContext::getMethodVTableIndex(GlobalDecl GD) {
+  GD = GD.getCanonicalDecl();
   MethodVTableIndicesTy::iterator I = MethodVTableIndices.find(GD);
   if (I != MethodVTableIndices.end())
     return I->second;
@@ -2503,6 +2504,8 @@ private:
     for (const auto &I : MethodInfoMap) {
       const CXXMethodDecl *MD = I.first;
       const MethodInfo &MI = I.second;
+      assert(MD == MD->getCanonicalDecl());
+
       // Skip the methods that the MostDerivedClass didn't override
       // and the entries shadowed by return adjusting thunks.
       if (MD->getParent() != MostDerivedClass || MI.Shadowed)
@@ -3737,6 +3740,8 @@ MicrosoftVTableContext::getMethodVFTableLocation(GlobalDecl GD) {
   if (isa<CXXDestructorDecl>(GD.getDecl()))
     assert(GD.getDtorType() == Dtor_Deleting);
 
+  GD = GD.getCanonicalDecl();
+
   MethodVFTableLocationsTy::iterator I = MethodVFTableLocations.find(GD);
   if (I != MethodVFTableLocations.end())
     return I->second;