[PATCH] Fix for bug 17427 - Assertion failed: "Computed __func__ length differs from type!"

[Alexey Bataev]

Hi Reid, Thanks for the review!

================
Comment at: lib/AST/Expr.cpp:521
@@ +520,3 @@
+    else
+      MC->mangleBlock(DC, BD, Out);
+    return Out.str();
----------------
rnk wrote:
> I believe this will assert in this code:
>   struct A {
>     const char *s;
>     A() {
>       const char *(^b)() = ^() {
>         return __func__;
>       };
>       s = b();
>   };
>   A a;
> You probably need to handle the ctor / dtor cases separately, as is done in CodeGenModule::getBlockMangledName. Using Ctor_Base and Dtor_Base should be correct. I don't think we should ever emit two different block implementations for the base ctor and complete ctor. =/
I'll add this test and fix the code to properly handle it.

================
Comment at: lib/CodeGen/CGExpr.cpp:2061
@@ +2060,3 @@
+    FnName = FnName.substr(1);
+  std::string NameItems[] = {
+      PredefinedExpr::getIdentTypeName(E->getIdentType()), FnName};
----------------
rnk wrote:
> I think this can be an array of StringRefs to avoid building two tmp strings.
Agree

================
Comment at: lib/CodeGen/CodeGenModule.cpp:2751-2752
@@ -2749,3 +2750,4 @@
   if (!LangOpts.WritableStrings && !LangOpts.Sanitize.Address &&
-      getCXXABI().getMangleContext().shouldMangleStringLiteral(S)) {
+      getCXXABI().getMangleContext().shouldMangleStringLiteral(S) &&
+      Name == ".str") {
     llvm::raw_svector_ostream Out(MangledNameBuffer);
----------------
rnk wrote:
> This change will cause duplicate string literals to not be merged across TUs on Windows. Just mangle the string literal if the ABI says we should.
Agree, I'll remove it

================
Comment at: test/CodeGenCXX/ms_wide_predefined_expr.cpp:3
@@ -2,3 +2,3 @@
 
-// CHECK: @"\01??_C at _19DPFBEKIN@?$AAf?$AAu?$AAn?$AAc?$AA?$AA@" = linkonce_odr unnamed_addr constant [5 x i16] [i16 102, i16 117, i16 110, i16 99, i16 0], align 2
+// CHECK: @"L__FUNCTION__.?func@@YAXXZ" = private unnamed_addr constant [5 x i16] [i16 102, i16 117, i16 110, i16 99, i16 0], align 2
 
----------------
rnk wrote:
> This test in particular should not change.
Agree, will revert it back

http://reviews.llvm.org/D5365