From: Simon Marchi <simon.marchi@ericsson.com>
To: <gdb-patches@sourceware.org>
Cc: Simon Marchi <simon.marchi@ericsson.com>
Subject: [PATCH] compile-loc2c: Fix uninitialized variable error
Date: Sat, 10 Jun 2017 19:49:00 -0000 [thread overview]
Message-ID: <1497124148-11187-1-git-send-email-simon.marchi@ericsson.com> (raw)
Compiling with clang gives this warning/error:
/home/emaisin/src/binutils-gdb/gdb/compile/compile-loc2c.c:731:6: error: variable 'uoffset' is uninitialized when used here [-Werror,-Wuninitialized]
uoffset += dwarf2_per_cu_text_offset (per_cu);
^~~~~~~
/home/emaisin/src/binutils-gdb/gdb/compile/compile-loc2c.c:669:23: note: initialize the variable 'uoffset' to silence this warning
uint64_t uoffset, reg;
^
= 0
I am really not sure if what this patch does is good, but it is my best
guess. DW_OP_addr means that there's an constant address provided by
the DWARF bytecode that should be pushed on the stack. That address is
considered skipped by the "op_ptr += addr_size", but it is never read.
uoffset is indeed read just after, without having been assigned first.
So I think the intent is to read the address, it was just omitted.
gdb/ChangeLog:
* compile/compile-loc2c.c (do_compile_dwarf_expr_to_c): Read
address when op is DW_OP_addr.
---
gdb/compile/compile-loc2c.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/gdb/compile/compile-loc2c.c b/gdb/compile/compile-loc2c.c
index a53214f..ead1003 100644
--- a/gdb/compile/compile-loc2c.c
+++ b/gdb/compile/compile-loc2c.c
@@ -722,6 +722,7 @@ do_compile_dwarf_expr_to_c (int indent, string_file &stream,
break;
case DW_OP_addr:
+ uoffset = extract_unsigned_integer (op_ptr, addr_size, byte_order);
op_ptr += addr_size;
/* Some versions of GCC emit DW_OP_addr before
DW_OP_GNU_push_tls_address. In this case the value is an
--
2.7.4
next reply other threads:[~2017-06-10 19:49 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-06-10 19:49 Simon Marchi [this message]
2017-06-25 17:24 ` Simon Marchi
2017-07-09 16:44 ` Tom Tromey
2017-07-09 18:28 ` Simon Marchi
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