For PR43213, track whether template parameters are implicit through

template instantiation so we know whether to mangle them in
lambda-expressions.

llvm-svn: 370991

Author: zygoloid

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

@@ -2337,6 +2337,7 @@ Decl *TemplateDeclInstantiator::VisitTemplateTypeParmDecl(
       D->getDepth() - TemplateArgs.getNumSubstitutedLevels(), D->getIndex(),
       D->getIdentifier(), D->wasDeclaredWithTypename(), D->isParameterPack());
   Inst->setAccess(AS_public);
+  Inst->setImplicit(D->isImplicit());
 
   if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
     TypeSourceInfo *InstantiatedDefaultArg =
@@ -2483,6 +2484,7 @@ Decl *TemplateDeclInstantiator::VisitNonTypeTemplateParmDecl(
         D->getPosition(), D->getIdentifier(), T, D->isParameterPack(), DI);
 
   Param->setAccess(AS_public);
+  Param->setImplicit(D->isImplicit());
   if (Invalid)
     Param->setInvalidDecl();
 
@@ -2626,6 +2628,7 @@ TemplateDeclInstantiator::VisitTemplateTemplateParmDecl(
                               D->getDefaultArgument().getTemplateNameLoc()));
   }
   Param->setAccess(AS_public);
+  Param->setImplicit(D->isImplicit());
 
   // Introduce this template parameter's instantiation into the instantiation
   // scope.

clang/test/CodeGenCXX/mangle-lambda-explicit-template-params.cpp

@@ -32,3 +32,10 @@ inline void inline_func() {
 void call_inline_func() {
   inline_func();
 }
+
+template<typename> void f() {
+  // CHECK: define linkonce_odr {{.*}} @_ZZ1fIiEvvENKUlT_E_clIiEEDaS0_(
+  auto x = [](auto){};
+  x(0);
+}
+void use_f() { f<int>(); }