From 0d6f4f1bb17e72b6bc0a7d781b2ca9fc1a6c4adb Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Tue, 6 Dec 2016 10:05:22 +0100
Subject: [PATCH] implements -d:nimdiff switch for seeing generated C code
 diffs

---
 compiler/cgen.nim | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/compiler/cgen.nim b/compiler/cgen.nim
index 118a10214d..6a60e87e90 100644
--- a/compiler/cgen.nim
+++ b/compiler/cgen.nim
@@ -1245,7 +1245,13 @@ proc shouldRecompile(code: Rope, cfile: string): bool =
   result = true
   if optForceFullMake notin gGlobalOptions:
     var objFile = toObjFile(cfile)
-    if writeRopeIfNotEqual(code, cfile): return
+
+    if not equalsFile(code, cfile):
+      if isDefined("nimdiff"):
+        copyFile(cfile, cfile & ".backup")
+        echo "diff ", cfile, ".backup ", cfile
+      writeRope(code, cfile)
+      return
     if existsFile(objFile) and os.fileNewer(objFile, cfile): result = false
   else:
     writeRope(code, cfile)