Fix the indentation of the first line of preprocessor output

The -E output from clang did not produce the correct indentation on the first line.
This is because MoveToLine returned false, and when this happens,
the regular process for producing initial indentation is skipped.

Thanks to Eli for suggesting a way to simplify this to a one-line change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173657 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 12 insertions, 1 deletions

diff --git a/lib/Frontend/PrintPreprocessedOutput.cpp b/lib/Frontend/PrintPreprocessedOutput.cpp
index cc8d935b52..e7b64973ad 100644
--- a/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -139,11 +139,15 @@ public:
                                 diag::Mapping Map, StringRef Str);
 
   bool HandleFirstTokOnLine(Token &Tok);
+
+  /// Move to the line of the provided source location. This will
+  /// return true if the output stream required adjustment or if
+  /// the requested location is on the first line.
   bool MoveToLine(SourceLocation Loc) {
     PresumedLoc PLoc = SM.getPresumedLoc(Loc);
     if (PLoc.isInvalid())
       return false;
-    return MoveToLine(PLoc.getLine());
+    return MoveToLine(PLoc.getLine()) || (PLoc.getLine() == 1);
   }
   bool MoveToLine(unsigned LineNo);
 
diff --git a/test/Preprocessor/first-line-indent.c b/test/Preprocessor/first-line-indent.c
new file mode 100644
index 0000000000..d220d57a28
--- /dev/null
+++ b/test/Preprocessor/first-line-indent.c
@@ -0,0 +1,7 @@
+       foo
+// RUN: %clang_cc1 -E %s | FileCheck -strict-whitespace %s
+       bar
+
+// CHECK: {{^       }}foo
+// CHECK: {{^       }}bar
+