nicer output in emcc when there are source code errors, plus test

1 files changed, 6 insertions, 2 deletions

diff --git a/emcc b/emcc
index 3e666bb3..e29946cf 100755
--- a/emcc
+++ b/emcc
@@ -363,9 +363,13 @@ try:
   # First, generate LLVM bitcode. For each input file, we get base.o with bitcode
   for input_file in input_files:
     if input_file.endswith(SOURCE_SUFFIXES):
-      args = newargs + ['-emit-llvm', '-c', input_file, '-o', in_temp(unsuffixed_basename(input_file) + '.o')]
+      output_file = in_temp(unsuffixed_basename(input_file) + '.o')
+      args = newargs + ['-emit-llvm', '-c', input_file, '-o', output_file]
       if DEBUG: print >> sys.stderr, "emcc running:", call, ' '.join(args)
-      Popen([call] + args).communicate()
+      Popen([call] + args).communicate() # let compiler frontend print directly, so colors are saved (PIPE kills that)
+      if not os.path.exists(output_file):
+        print >> sys.stderr, 'emcc: compiler frontend failed to generate LLVM bitcode, halting'
+        sys.exit(1)
     else: # bitcode
       if input_file.endswith(('.bc', '.o')):
         shutil.copyfile(input_file, in_temp(unsuffixed_basename(input_file) + '.o'))