clang-format: Don't exit with failure on empty files.

Also let clang-format-diff.py detect errors based on clang-format's
return code. Otherwise messages like "Can't find usable .clang-format,
falling back to LLVM style" can make it fail, which might be undesired.

Patch by Alp Toker. Thank you!

llvm-svn: 192184

2 files changed, 3 insertions, 2 deletions

diff --git a/clang/tools/clang-format/ClangFormat.cpp b/clang/tools/clang-format/ClangFormat.cpp
index e08aa2d5b8d..2ca2bed61a4 100644
--- a/clang/tools/clang-format/ClangFormat.cpp
+++ b/clang/tools/clang-format/ClangFormat.cpp
@@ -186,7 +186,7 @@ static bool format(std::string FileName) {
     return true;
   }
   if (Code->getBufferSize() == 0)
-    return true; // Empty files are formatted correctly.
+    return false; // Empty files are formatted correctly.
   FileID ID = createInMemoryFile(FileName, Code.get(), Sources, Files);
   std::vector<CharSourceRange> Ranges;
   if (fillRanges(Sources, ID, Code.get(), Ranges))
diff --git a/clang/tools/clang-format/clang-format-diff.py b/clang/tools/clang-format/clang-format-diff.py
index 90723d217b8..ca949b84ef9 100755
--- a/clang/tools/clang-format/clang-format-diff.py
+++ b/clang/tools/clang-format/clang-format-diff.py
@@ -81,7 +81,8 @@ def main():
     stdout, stderr = p.communicate()
     if stderr:
       print stderr
-      return
+    if p.returncode != 0:
+      sys.exit(p.returncode);
 
 
 if __name__ == '__main__':