From 52bf80a1c9ceda3e118d67b2683cdb3b402a1a18 Mon Sep 17 00:00:00 2001
From: jilles <jilles@FreeBSD.org>
Date: Fri, 16 Oct 2009 16:17:57 +0000
Subject: [PATCH] sh: Show more information about syntax errors in command
 substitution: the line number where the command substitution started. This
 applies to both the $() and `` forms but is most useful for `` because the
 other line number is relative to the enclosed text there. (For older
 versions, -v can be used as a workaround.)

---
 bin/sh/parser.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/bin/sh/parser.c b/bin/sh/parser.c
index 9e861620e5f7..8dd1e7a72367 100644
--- a/bin/sh/parser.c
+++ b/bin/sh/parser.c
@@ -1308,11 +1308,16 @@ parsebackq: {
 	struct jmploc *const savehandler = handler;
 	int savelen;
 	int saveprompt;
+	const int bq_startlinno = plinno;
 
 	if (setjmp(jmploc.loc)) {
 		if (str)
 			ckfree(str);
 		handler = savehandler;
+		if (exception == EXERROR) {
+			startlinno = bq_startlinno;
+			synerror("Error in command substitution");
+		}
 		longjmp(handler->loc, 1);
 	}
 	INTOFF;