Sema: Propagate the mangling number into instantiations

We would lose track of the mangling number assigned to the original
declaration which would cause us to create manglings that didn't match
the Itanium C++ specification.

e.g. Two static fields with the same name inside of a function template
would receive the same mangling with LLVM fixing up the second field so
they wouldn't collide.  This would create an incompatibility with other
compilers following the Itanium ABI.

I've confirmed that the new mangling is identical to the ones generated
by icc and gcc.

N.B. This was uncovered while working on Microsoft mangler.

llvm-svn: 196368

1 files changed, 22 insertions, 0 deletions

diff --git a/clang/test/CodeGenCXX/mangle-template.cpp b/clang/test/CodeGenCXX/mangle-template.cpp
index 3b7f3027f6c..9bd74b54a5b 100644
--- a/clang/test/CodeGenCXX/mangle-template.cpp
+++ b/clang/test/CodeGenCXX/mangle-template.cpp
@@ -182,3 +182,25 @@ namespace test13 {
   template short returnShort<-32768>();
   // CHECK: @_ZN6test1311returnShortILsn32768EEEsv()
 }
+
+namespace test14 {
+  template <typename> inline int inl(bool b) {
+    if (b) {
+      static struct {
+        int field;
+      } a;
+      // CHECK: @_ZZN6test143inlIvEEibE1a
+
+      return a.field;
+    } else {
+      static struct {
+        int field;
+      } a;
+      // CHECK: @_ZZN6test143inlIvEEibE1a_0
+
+      return a.field;
+    }
+  }
+
+  int call(bool b) { return inl<void>(b); }
+}