Sema: Disable template instantiation once a fatal error is raised

Fatal errors disable all further diagnostics.  Continuing to permit
template instantiation does nothing but make it take longer for clang to
finish with the TU.

Instead, halt all further instantiation.

Fixed in PR22396.

llvm-svn: 227556

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index 6ac7175cf30..ed0d5a54e80 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -207,6 +207,12 @@ void Sema::InstantiatingTemplate::Initialize(
     sema::TemplateDeductionInfo *DeductionInfo) {
   SavedInNonInstantiationSFINAEContext =
       SemaRef.InNonInstantiationSFINAEContext;
+  // Don't allow further instantiation if a fatal error has occcured.  Any
+  // diagnostics we might have raised will not be visible.
+  if (SemaRef.Diags.hasFatalErrorOccurred()) {
+    Invalid = true;
+    return;
+  }
   Invalid = CheckInstantiationDepth(PointOfInstantiation, InstantiationRange);
   if (!Invalid) {
     ActiveTemplateInstantiation Inst;