llvm-cov: Handle functions with no line number

Functions may in an instrumented binary but not in the original source
when they're inserted by the compiler or the runtime. These functions
aren't meaningful to the user, so teach llvm-cov to skip over them
instead of crashing.

llvm-svn: 204863

1 files changed, 5 insertions, 0 deletions

diff --git a/llvm/lib/IR/GCOV.cpp b/llvm/lib/IR/GCOV.cpp
index dc9cb4b2a81..f69bdc4f8cc 100644
--- a/llvm/lib/IR/GCOV.cpp
+++ b/llvm/lib/IR/GCOV.cpp
@@ -308,6 +308,11 @@ void GCOVFunction::dump() const {
 /// collectLineCounts - Collect line counts. This must be used after
 /// reading .gcno and .gcda files.
 void GCOVFunction::collectLineCounts(FileInfo &FI) {
+  // If the line number is zero, this is a function that doesn't actually appear
+  // in the source file, so there isn't anything we can do with it.
+  if (LineNumber == 0)
+    return;
+
   for (SmallVectorImpl<GCOVBlock *>::iterator I = Blocks.begin(),
          E = Blocks.end(); I != E; ++I)
     (*I)->collectLineCounts(FI);