Introduce -Wreserved-identifier

Warn when a declaration uses an identifier that doesn't obey the reserved
identifier rule from C and/or C++.

Differential Revision: https://reviews.llvm.org/D93095

1 files changed, 5 insertions, 6 deletions

diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index 4330024e..8893bd2 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -739,18 +739,17 @@ getRequiredQualification(ASTContext &Context, const DeclContext *CurContext,
 // Filter out names reserved for the implementation if they come from a
 // system header.
 static bool shouldIgnoreDueToReservedName(const NamedDecl *ND, Sema &SemaRef) {
-  const IdentifierInfo *Id = ND->getIdentifier();
-  if (!Id)
-    return false;
-
+  ReservedIdentifierStatus Status = ND->isReserved(SemaRef.getLangOpts());
   // Ignore reserved names for compiler provided decls.
-  if (Id->isReservedName() && ND->getLocation().isInvalid())
+  if ((Status != ReservedIdentifierStatus::NotReserved) &&
+      (Status != ReservedIdentifierStatus::StartsWithUnderscoreAtGlobalScope) &&
+      ND->getLocation().isInvalid())
     return true;
 
   // For system headers ignore only double-underscore names.
   // This allows for system headers providing private symbols with a single
   // underscore.
-  if (Id->isReservedName(/*doubleUnderscoreOnly=*/true) &&
+  if (Status == ReservedIdentifierStatus::StartsWithDoubleUnderscore &&
       SemaRef.SourceMgr.isInSystemHeader(
           SemaRef.SourceMgr.getSpellingLoc(ND->getLocation())))
     return true;