Fix PCH bug with member templates of local classes in nontemplate functions.

As noted by Richard in the post:
http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20130624/082605.html, the following code should not add an entry
into PendingLocalImplicitInstantiations, since local instantiations
should only occur within the context of other instantiations:

int foo(double y) {
   struct Lambda {
      template<class T> T operator()(T t) const { return t; };
   } lambda;
   return lambda(y);
}

Hence the attached code does the following:
  1) In MarkFunctionReferenced, check if ActiveInstantiations.size() 
      is non-zero before adding to PendingLocalImplicitInstantiations.
  2) In InstantiateFunctionDefinition, we swap out/in
      PendingLocalImplicitInstantiations so that only those 
      pending local instantiations that are added during the instantiation
      of the current function are instantiated recursively.

llvm-svn: 184903

1 files changed, 55 insertions, 0 deletions

diff --git a/clang/test/PCH/cxx-local-templates.cpp b/clang/test/PCH/cxx-local-templates.cpp
new file mode 100644
index 00000000000..277ad831099
--- /dev/null
+++ b/clang/test/PCH/cxx-local-templates.cpp
@@ -0,0 +1,55 @@
+// RUN: %clang_cc1 -pedantic-errors -std=c++11 -emit-pch %s -o %t-cxx11

+// RUN: %clang_cc1 -ast-print -pedantic-errors -std=c++11 -include-pch %t-cxx11  %s | FileCheck -check-prefix=CHECK-PRINT %s

+

+#ifndef HEADER_INCLUDED

+

+#define HEADER_INCLUDED

+

+int nontemplate_test(double d) {

+  struct Local {

+    template<class T> T foo(T t) {

+      return t;

+    }

+  };

+  return Local{}.foo(d);

+}

+

+template<class U>

+U template_test(U d) {

+  struct Local {

+    template<class T> T foo(T t) {

+      return t;

+    }

+  };

+  return Local{}.foo(d);

+}

+

+int nested_local() {

+  struct Inner1 {

+    int inner1_foo(char c) {

+      struct Inner2 {

+        template<class T> T inner2_foo(T t) {

+          return t;

+        }

+      };

+      return Inner2{}.inner2_foo(3.14);

+    }

+  };

+  return Inner1{}.inner1_foo('a');

+}

+

+#else

+

+// CHECK-PRINT: U template_test

+

+// CHECK-PRINT: int nontemplate_test(double)

+

+int nontemplate_test(double);

+

+template double template_test(double);

+int test2(int y) {

+  return nontemplate_test(y) + template_test(y);

+}

+

+

+#endif