Fix PR8625 and correctly interpret member-calls to static members when

producing warnings.

This feels really fragile, and I've not audited all other argument index-based
warnings. I suspect we'll grow this bug on another warning eventually. It might
be nice to adjust the argument indices when building up the attribute AST node,
as we already have to remember about the 'this' argument within that code to
produce correct errors.

llvm-svn: 119340

1 files changed, 10 insertions, 6 deletions

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 83d7c0760ef..bce28c2c91d 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -1090,12 +1090,16 @@ Sema::CheckPrintfScanfArguments(const CallExpr *TheCall, bool HasVAListArg,
   // of member functions is counted. However, it doesn't appear in our own
   // lists, so decrement format_idx in that case.
   if (isa<CXXMemberCallExpr>(TheCall)) {
-    // Catch a format attribute mistakenly referring to the object argument.
-    if (format_idx == 0)
-      return;
-    --format_idx;
-    if(firstDataArg != 0)
-      --firstDataArg;
+    const CXXMethodDecl *method_decl =
+      dyn_cast<CXXMethodDecl>(TheCall->getCalleeDecl());
+    if (method_decl && method_decl->isInstance()) {
+      // Catch a format attribute mistakenly referring to the object argument.
+      if (format_idx == 0)
+        return;
+      --format_idx;
+      if(firstDataArg != 0)
+        --firstDataArg;
+    }
   }
 
   // CHECK: printf/scanf-like function is called with no format string.