| Bug #59906 | 5.5 debug builds broken by extra/comp_err.c | ||
|---|---|---|---|
| Submitted: | 2 Feb 2011 22:38 | Modified: | 2 Mar 2011 3:44 |
| Reporter: | Mark Callaghan | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Compiling | Severity: | S3 (Non-critical) |
| Version: | 5.5 | OS: | Any |
| Assigned to: | Tor Didriksen | CPU Architecture: | Any |
| Tags: | debug | ||
[3 Feb 2011 9:01]
Valeriy Kravchuk
I can not repeat this problem with current mysql-5.5 tree on 32-bit Ubuntu 10.04 using:
gcc (Ubuntu 4.4.3-4ubuntu5) 4.4.3
for whatever reason. But code in extra/comp_err.c is still the same:
static int create_header_files(struct errors *error_head)
{
uint er_last;
FILE *er_definef, *sql_statef, *er_namef;
struct errors *tmp_error;
struct message *er_msg;
const char *er_text;
DBUG_ENTER("create_header_files");
LINT_INIT(er_last);
...
and, theoretically, LINT_INIT macro defined in include/my_global.h as follows:
/*
Deprecated workaround for false-positive uninitialized variables
warnings. Those should be silenced using tool-specific heuristics.
Enabled by default for g++ due to the bug referenced below.
*/
#if defined(_lint) || defined(FORCE_INIT_OF_VARS) || \
(defined(__GNUC__) && defined(__cplusplus))
#define LINT_INIT(var) var= 0
#else
#define LINT_INIT(var)
#endif
should take care of initialization... but I think your suggested change in code will do that even better.
So, let's say this is verified by code review.
[2 Mar 2011 3:44]
Paul DuBois
Noted in 5.5.11, 5.6.2 changelogs. On some systems, debug builds of comp_err.c could fail due to an uninitialized variable. CHANGESET - http://lists.mysql.com/commits/131432
Description: cmake -DWITH_DEBUG builds for 5.5.8 fail for me because of a compiler warning about a potentially unused variable in extra/comp_err.c How to repeat: system uses gcc 4.1.2, centos 5.2, x86-64 cmake . \ -DBUILD_CONFIG=mysql_release \ -DWITH_EMBEDDED_SERVER=0 -DWITH_PERFSCHEMA_STORAGE_ENGINE=1 make output is cc1: warnings being treated as errors /s/bld/558orig/extra/comp_err.c: In function ‘create_header_files’: /s/bld/558orig/extra/comp_err.c:222: warning: ‘er_last’ may be used uninitialized in this function make[2]: *** [extra/CMakeFiles/comp_err.dir/comp_err.c.o] Error 1 make[1]: *** [extra/CMakeFiles/comp_err.dir/all] Error 2 make: *** [all] Error 2 Suggested fix: This might be a kludge, but I just want my builds diff --git a/extra/comp_err.c b/extra/comp_err.c index 4c40e70..8b7ddbf 100644 --- a/extra/comp_err.c +++ b/extra/comp_err.c @@ -219,7 +219,7 @@ static void print_escaped_string(FILE *f, const char *str) static int create_header_files(struct errors *error_head) { - uint er_last; + uint er_last=0; FILE *er_definef, *sql_statef, *er_namef; struct errors *tmp_error; struct message *er_msg;