Fix my earlier commit to work with escaped newlines and leave breadcrumbs

in case we want to make a world where we can check intermediate instantiations
for this kind of breadcrumb.

llvm-svn: 127221

3 files changed, 27 insertions, 9 deletions

diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 4bfb388081d..0846845e26d 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -592,6 +592,27 @@ Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) {
   return Builder;
 }
 
+/// \brief Looks through the macro-instantiation chain for the given
+/// location, looking for a macro instantiation with the given name.
+/// If one is found, returns true and sets the location to that
+/// instantiation loc.
+bool Sema::findMacroSpelling(SourceLocation &locref, llvm::StringRef name) {
+  SourceLocation loc = locref;
+  if (!loc.isMacroID()) return false;
+
+  // There's no good way right now to look at the intermediate
+  // instantiations, so just jump to the instantiation location.
+  loc = getSourceManager().getInstantiationLoc(loc);
+
+  // If that's written with the name, stop here.
+  llvm::SmallVector<char, 16> buffer;
+  if (getPreprocessor().getSpelling(loc, buffer) == name) {
+    locref = loc;
+    return true;
+  }
+  return false;
+}
+
 /// \brief Determines the active Scope associated with the given declaration
 /// context.
 ///
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index c4218c3365d..8f79428eae1 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -5261,9 +5261,8 @@ bool Sema::DiagnoseConditionalForNull(Expr *LHS, Expr *RHS,
     // In this case, check to make sure that we got here from a "NULL"
     // string in the source code.
     NullExpr = NullExpr->IgnoreParenImpCasts();
-    SourceLocation Loc =
-      getSourceManager().getInstantiationLoc(NullExpr->getExprLoc());
-    if (getPreprocessor().getSpelling(Loc) != "NULL")
+    SourceLocation loc = NullExpr->getExprLoc();
+    if (!findMacroSpelling(loc, "NULL"))
       return false;
   }
 
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index 772a5575459..11e7c313829 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -95,12 +95,10 @@ static void diagnoseBadTypeAttribute(Sema &S, const AttributeList &attr,
 
   // The GC attributes are usually written with macros;  special-case them.
   if (useInstantiationLoc && loc.isMacroID() && attr.getParameterName()) {
-    SourceLocation instLoc = S.getSourceManager().getInstantiationLoc(loc);
-    llvm::StringRef macro = S.getPreprocessor().getSpelling(instLoc);
-    if ((macro == "__strong" && attr.getParameterName()->isStr("strong")) ||
-        (macro == "__weak" && attr.getParameterName()->isStr("weak"))) {
-      loc = instLoc;
-      name = macro;
+    if (attr.getParameterName()->isStr("strong")) {
+      if (S.findMacroSpelling(loc, "__strong")) name = "__strong";
+    } else if (attr.getParameterName()->isStr("weak")) {
+      if (S.findMacroSpelling(loc, "__weak")) name = "__weak";
     }
   }