[clang] Check for nullptr when instantiating late attrs

This was already done in SemaTemplateInstantiateDecl.cpp, but not in
SemaTemplateInstantiate.cpp.

Anecdotally I've seen some clangd crashes where coredumps point to this
being a problem, but I cannot reproduce this so far.

Differential Revision: https://reviews.llvm.org/D94933

diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index cb74f08..7679063 100644 (file)
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -2796,7 +2796,8 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
 
     Attr *NewAttr =
       instantiateTemplateAttribute(I->TmplAttr, Context, *this, TemplateArgs);
-    I->NewDecl->addAttr(NewAttr);
+    if (NewAttr)
+      I->NewDecl->addAttr(NewAttr);
     LocalInstantiationScope::deleteScopes(I->Scope,
                                           Instantiator.getStartingScope());
   }