From c2add96c8dc9d5346725080fad774810c14839a6 Mon Sep 17 00:00:00 2001 From: Andy Green Date: Wed, 13 Jun 2018 07:34:07 +0800 Subject: gcc8.1: fix strncat warning MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ../ui-ssdiff.c: In function ‘replace_tabs’: ../ui-ssdiff.c:142:4: warning: ‘strncat’ output truncated copying between 1 and 8 bytes from a string of length 8 [-Wstringop-truncation] strncat(result, spaces, 8 - (strlen(result) % 8)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Actually the strncat that was there before intends that its stock of spaces gets truncated, and it's not a problem. However gcc8.1 is also right, normally truncation is undesirable. Make the code do the padding explicitly. Signed-off-by: Andy Green --- ui-ssdiff.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/ui-ssdiff.c b/ui-ssdiff.c index 7f261ed..e520b95 100644 --- a/ui-ssdiff.c +++ b/ui-ssdiff.c @@ -118,7 +118,6 @@ static char *replace_tabs(char *line) int n_tabs = 0; int i; char *result; - char *spaces = " "; if (linelen == 0) { result = xmalloc(1); @@ -138,8 +137,17 @@ static char *replace_tabs(char *line) strcat(result, prev_buf); break; } else { + char *p; + int n; + strncat(result, prev_buf, cur_buf - prev_buf); - strncat(result, spaces, 8 - (strlen(result) % 8)); + + n = strlen(result); + p = result + n; + n = 8 - (n % 8); + while (n--) + *p++ = ' '; + *p = '\0'; } prev_buf = cur_buf + 1; } -- cgit v1.2.1