From ec4985a5733c9e65e162ece35dca90b37b193f1c Mon Sep 17 00:00:00 2001
From: Araq <rumpf_a@web.de>
Date: Thu, 18 Oct 2018 16:53:49 +0200
Subject: [PATCH] fixes #7972

---
 compiler/transf.nim          | 23 +++++++++++++----------
 tests/trmacros/tstmtlist.nim | 15 +++++++++++++++
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/compiler/transf.nim b/compiler/transf.nim
index 6b6335129..473c9f2bd 100644
--- a/compiler/transf.nim
+++ b/compiler/transf.nim
@@ -199,17 +199,20 @@ proc transformVarSection(c: PTransf, v: PNode): PTransNode =
       result[i] = defs
 
 proc transformConstSection(c: PTransf, v: PNode): PTransNode =
-  result = newTransNode(v)
-  for i in countup(0, sonsLen(v)-1):
-    var it = v.sons[i]
-    if it.kind == nkCommentStmt:
-      result[i] = PTransNode(it)
-    else:
-      if it.kind != nkConstDef: internalError(c.graph.config, it.info, "transformConstSection")
-      if it.sons[0].kind != nkSym:
-        internalError(c.graph.config, it.info, "transformConstSection")
+  result = PTransNode(v)
+  when false:
+    result = newTransNode(v)
+    for i in countup(0, sonsLen(v)-1):
+      var it = v.sons[i]
+      if it.kind == nkCommentStmt:
+        result[i] = PTransNode(it)
+      else:
+        if it.kind != nkConstDef: internalError(c.graph.config, it.info, "transformConstSection")
+        if it.sons[0].kind != nkSym:
+          debug it.sons[0]
+          internalError(c.graph.config, it.info, "transformConstSection")
 
-      result[i] = PTransNode(it)
+        result[i] = PTransNode(it)
 
 proc hasContinue(n: PNode): bool =
   case n.kind
diff --git a/tests/trmacros/tstmtlist.nim b/tests/trmacros/tstmtlist.nim
index 751acb79a..8261e7c45 100644
--- a/tests/trmacros/tstmtlist.nim
+++ b/tests/trmacros/tstmtlist.nim
@@ -17,3 +17,18 @@ if true:
   writeLine stdout, "2"
   write stdout, "3"
   echo "4"
+
+# bug #7972
+
+template optimizeLogWrites*{
+  write(f, x)
+  write(f, y)
+}(x, y: string{lit}, f: File) =
+  write(f, x & y)
+
+proc foo() =
+  const N = 1
+  stdout.write("")
+  stdout.write("")
+
+foo()