From: Rob Pike <r@golang.org>
Date: Fri, 11 Jul 2014 15:16:00 +0000 (+0000)
Subject: ld: change DWARF output for structs
X-Git-Tag: go1.4beta1~1111
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=125d1e9269572135d078ee128b239280c7101e6c;p=gostls13.git

ld: change DWARF output for structs
The debug/dwarf package cannot parse the format generated here,
but the format can be changed so it does.
After this edit, tweaking the expression defining the offset
of a struct field, the dwarf package can parse the tables (again?).

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/105710043
---

diff --git a/src/cmd/ld/dwarf.c b/src/cmd/ld/dwarf.c
index a9f9329932..90c6725bc7 100644
--- a/src/cmd/ld/dwarf.c
+++ b/src/cmd/ld/dwarf.c
@@ -835,11 +835,8 @@ newmemberoffsetattr(DWDie *die, int32 offs)
 	int i;
 
 	i = 0;
-	if (offs != 0) {
-		block[i++] = DW_OP_consts;
-		i += sleb128enc(offs, block+i);
-		block[i++] = DW_OP_plus;
-	}
+	block[i++] = DW_OP_plus_uconst;
+	i += uleb128enc(offs, block+i);
 	newattr(die, DW_AT_data_member_location, DW_CLS_BLOCK, i, mal(i));
 	memmove(die->attr->data, block, i);
 }