Avoid assert when a non-static member function is qualified with __unaligned

Under -fms-extensions __unaligned is a type-qualifier that can be applied to a
non-static member function declaration.

This causes an assertion when mangling the name under Itanium, where that
qualifier is not mangled.

This patch justs makes the minimal change to avoid the crash and avoid mangling
__unaligned, as it currently happens with non-member functions.

Differential Revision: https://reviews.llvm.org/D31976

llvm-svn: 300686

2 files changed, 23 insertions, 1 deletions

diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index 29fcdd7be92..7db0b4d8e4f 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -1455,10 +1455,12 @@ void CXXNameMangler::mangleNestedName(const NamedDecl *ND,
   Out << 'N';
   if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(ND)) {
     Qualifiers MethodQuals =
-        Qualifiers::fromCVRMask(Method->getTypeQualifiers());
+        Qualifiers::fromCVRUMask(Method->getTypeQualifiers());
     // We do not consider restrict a distinguishing attribute for overloading
     // purposes so we must not mangle it.
     MethodQuals.removeRestrict();
+    // __unaligned is not currently mangled in any way, so remove it.
+    MethodQuals.removeUnaligned();
     mangleQualifiers(MethodQuals);
     mangleRefQualifier(Method->getRefQualifier());
   }
diff --git a/clang/test/CodeGenCXX/unaligned-duplicated-mangle-name.cpp b/clang/test/CodeGenCXX/unaligned-duplicated-mangle-name.cpp
new file mode 100644
index 00000000000..a23e6a47ab0
--- /dev/null
+++ b/clang/test/CodeGenCXX/unaligned-duplicated-mangle-name.cpp
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -triple %itanium_abi_triple -fms-extensions -emit-llvm-only %s -verify
+
+struct A
+{
+    int x;
+    void foo() __unaligned;
+    void foo();
+};
+
+void A::foo() __unaligned
+{
+    this->x++;
+}
+
+void A::foo() // expected-error {{definition with same mangled name as another definition}}
+              // expected-note@-6 {{previous definition is here}}
+{
+    this->x++;
+}
+