From: Tom de Vries <tdevries@suse.de>
Date: Mon, 13 Nov 2023 08:31:20 +0000 (+0100)
Subject: [gdb/tui] Fix Wmaybe-uninitialized in tui_find_disassembly_address
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6b682bbf86f37982ce1d270fb47f363413490bda;p=binutils-gdb.git

[gdb/tui] Fix Wmaybe-uninitialized in tui_find_disassembly_address

When building gdb with -O2, we run into:
...
gdb/tui/tui-disasm.c: In function ‘CORE_ADDR tui_find_disassembly_address \
  (gdbarch*, CORE_ADDR, int)’:
gdb/tui/tui-disasm.c:293:7: warning: ‘last_addr’ may be used uninitialized \
  in this function [-Wmaybe-uninitialized]
       if (last_addr < pc)
       ^~
...

The warning triggers since commit 72535eb14bd ("[gdb/tui] Fix segfault in
tui_find_disassembly_address").

Fix the warning by ensuring that last_addr is initialized at the point of
use:
...
+      last_addr = asm_lines.back ().addr;
       if (last_addr < pc)
...

Tested on x86_64-linux.
---

diff --git a/gdb/tui/tui-disasm.c b/gdb/tui/tui-disasm.c
index 9965ae134fe..dcafbfbb802 100644
--- a/gdb/tui/tui-disasm.c
+++ b/gdb/tui/tui-disasm.c
@@ -278,7 +278,6 @@ tui_find_disassembly_address (struct gdbarch *gdbarch, CORE_ADDR pc, int from)
 	  /* Take the best possible match we have.  */
 	  new_low = *possible_new_low;
 	  next_addr = tui_disassemble (gdbarch, asm_lines, new_low, max_lines);
-	  last_addr = asm_lines.back ().addr;
 	}
 
       /* The following walk forward assumes that ASM_LINES contains exactly
@@ -290,6 +289,7 @@ tui_find_disassembly_address (struct gdbarch *gdbarch, CORE_ADDR pc, int from)
 	 We keep the disassembled instructions in the 'lines' window
 	 and shift it downward (increasing its addresses).  */
       int pos = max_lines - 1;
+      last_addr = asm_lines.back ().addr;
       if (last_addr < pc)
 	do
 	  {