valgrind-developers

[Mark W. <ma...@so...>]

https://sourceware.org/git/gitweb.cgi?p=valgrind.git;h=d7db69fbf482149e18ed1977df41fe320f5cbef2

commit d7db69fbf482149e18ed1977df41fe320f5cbef2
Author: Mark Wielaard <ma...@kl...>
Date:   Thu Nov 14 12:25:27 2024 +0100

    coregrind/m_gdbserver/remote-utils.c (prepare_resume_reply): Use memcpy
    
    GCC8 (but apparently not later versions) complain about the use of
    strncpy when not actually copying a string:
    
    remote-utils.c:1140:14: warning: 'char* strncpy(char*, const char*, size_t)' output truncated before terminating nul copying 6 bytes from a string of the same length [-Wstringop-truncation]
              strncpy (buf, "watch:", 6);
              ~~~~~~~~^~~~~~~~~~~~~~~~~~
    
    This is "harmless" because buf is large enough and we will add more
    chars (including a zero terminator) later. But using strncpy here is a
    bit odd because we don't really want to copy a string, but an array of
    6 chars. So use memcpy here to do so, simplyfing the code.

Diff:
---
 coregrind/m_gdbserver/remote-utils.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/coregrind/m_gdbserver/remote-utils.c b/coregrind/m_gdbserver/remote-utils.c
index b22dc4482b..8dfc768d49 100644
--- a/coregrind/m_gdbserver/remote-utils.c
+++ b/coregrind/m_gdbserver/remote-utils.c
@@ -1137,7 +1137,7 @@ void prepare_resume_reply (char *buf, char status, unsigned char sig)
          CORE_ADDR addr;
          int i;
 
-         strncpy (buf, "watch:", 6);
+         VG_(memcpy) (buf, "watch:", 6);
          buf += 6;
 
          addr = valgrind_stopped_data_address ();