From: David Majnemer <david.majnemer@gmail.com>
Date: Mon, 18 May 2015 00:05:25 +0000 (+0000)
Subject: [MS ABI] Function encodings are always encoded in template arguments
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5a3b2f60a8babd6ba866498dce44d39fcebeb7a0;p=clang

[MS ABI] Function encodings are always encoded in template arguments

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@237547 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index b8327af6fa..818ea30b32 100644
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -250,7 +250,7 @@ public:
 
   void mangle(const NamedDecl *D, StringRef Prefix = "\01?");
   void mangleName(const NamedDecl *ND);
-  void mangleFunctionEncoding(const FunctionDecl *FD);
+  void mangleFunctionEncoding(const FunctionDecl *FD, bool ShouldMangle);
   void mangleVariableEncoding(const VarDecl *VD);
   void mangleMemberDataPointer(const CXXRecordDecl *RD, const ValueDecl *VD);
   void mangleMemberFunctionPointer(const CXXRecordDecl *RD,
@@ -383,7 +383,7 @@ void MicrosoftCXXNameMangler::mangle(const NamedDecl *D, StringRef Prefix) {
   Out << Prefix;
   mangleName(D);
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
-    mangleFunctionEncoding(FD);
+    mangleFunctionEncoding(FD, Context.shouldMangleDeclName(FD));
   else if (const VarDecl *VD = dyn_cast<VarDecl>(D))
     mangleVariableEncoding(VD);
   else {
@@ -396,7 +396,8 @@ void MicrosoftCXXNameMangler::mangle(const NamedDecl *D, StringRef Prefix) {
   }
 }
 
-void MicrosoftCXXNameMangler::mangleFunctionEncoding(const FunctionDecl *FD) {
+void MicrosoftCXXNameMangler::mangleFunctionEncoding(const FunctionDecl *FD,
+                                                     bool ShouldMangle) {
   // <type-encoding> ::= <function-class> <function-type>
 
   // Since MSVC operates on the type as written and not the canonical type, it
@@ -411,13 +412,14 @@ void MicrosoftCXXNameMangler::mangleFunctionEncoding(const FunctionDecl *FD) {
   // extern "C" functions can hold entities that must be mangled.
   // As it stands, these functions still need to get expressed in the full
   // external name.  They have their class and type omitted, replaced with '9'.
-  if (Context.shouldMangleDeclName(FD)) {
+  if (ShouldMangle) {
     // First, the function class.
     mangleFunctionClass(FD);
 
     mangleFunctionType(FT, FD);
-  } else
+  } else {
     Out << '9';
+  }
 }
 
 void MicrosoftCXXNameMangler::mangleVariableEncoding(const VarDecl *VD) {
@@ -556,7 +558,7 @@ MicrosoftCXXNameMangler::mangleMemberFunctionPointer(const CXXRecordDecl *RD,
       }
     } else {
       mangleName(MD);
-      mangleFunctionEncoding(MD);
+      mangleFunctionEncoding(MD, /*ShouldMangle=*/true);
     }
   } else {
     // Null single inheritance member functions are encoded as a simple nullptr.
@@ -1171,10 +1173,13 @@ void MicrosoftCXXNameMangler::mangleTemplateArg(const TemplateDecl *TD,
           cast<ValueDecl>(ND));
     } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
       const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
-      if (MD && MD->isInstance())
+      if (MD && MD->isInstance()) {
         mangleMemberFunctionPointer(MD->getParent()->getMostRecentDecl(), MD);
-      else
-        mangle(FD, "$1?");
+      } else {
+        Out << "$1?";
+        mangleName(FD);
+        mangleFunctionEncoding(FD, /*ShouldMangle=*/true);
+      }
     } else {
       mangle(ND, TA.getParamTypeForDecl()->isReferenceType() ? "$E?" : "$1?");
     }
diff --git a/test/CodeGenCXX/mangle-ms.cpp b/test/CodeGenCXX/mangle-ms.cpp
index 662278b303..ed2172b7c4 100644
--- a/test/CodeGenCXX/mangle-ms.cpp
+++ b/test/CodeGenCXX/mangle-ms.cpp
@@ -380,3 +380,9 @@ void TypedefNewDelete::operator delete[](void *) { }
 
 void __vectorcall vector_func() { }
 // CHECK-DAG: @"\01?vector_func@@YQXXZ"
+
+template <void (*)(void)>
+void fn_tmpl() {}
+
+template void fn_tmpl<extern_c_func>();
+// CHECK-DAG: @"\01??$fn_tmpl@$1?extern_c_func@@YAXXZ@@YAXXZ"