When the ASTImporter imports a source location, it avoids importing macro

expansions by calling getSpellingLoc(). That's great in most cases, but for
macros defined in the '<built-in>' source file, the source file is invalid
and does not import correctly, causing an assertion failure (the assertion
is Invalid SLocOffset or bad function choice).

A more reliable way to avoid this is to use getFileLoc(), which does not
return built-in locations. This avoids the crash but still preserves valid
source locations.

I've added a testcase that covers the previously crashing scenario.

https://reviews.llvm.org/D26054

llvm-svn: 286144

1 files changed, 2 insertions, 2 deletions

diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index 9e17c0c3de5..e783854448b 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -6943,10 +6943,10 @@ SourceLocation ASTImporter::Import(SourceLocation FromLoc) {
 
   SourceManager &FromSM = FromContext.getSourceManager();
   
-  // For now, map everything down to its spelling location, so that we
+  // For now, map everything down to its file location, so that we
   // don't have to import macro expansions.
   // FIXME: Import macro expansions!
-  FromLoc = FromSM.getSpellingLoc(FromLoc);
+  FromLoc = FromSM.getFileLoc(FromLoc);
   std::pair<FileID, unsigned> Decomposed = FromSM.getDecomposedLoc(FromLoc);
   SourceManager &ToSM = ToContext.getSourceManager();
   FileID ToFileID = Import(Decomposed.first);