| Bug #57562 | Strict aliasing warning in vio_get_normalized_ip_string() | ||
|---|---|---|---|
| Submitted: | 19 Oct 2010 10:58 | Modified: | 21 Oct 2010 15:34 |
| Reporter: | Magnus Blåudd | Email Updates: | |
| Status: | Verified | Impact on me: | |
| Category: | MySQL Server | Severity: | S3 (Non-critical) |
| Version: | 5.5.7-rc | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
| Triage: | Triaged: D4 (Minor) | ||
[19 Oct 2010 11:01]
Davi Arnaut
Strict aliasing violations are being aggregated in Bug#42733. Also, the union trick only works on a couple of compilers, its not standard. The right fix is a simple cast to void...
[19 Oct 2010 11:03]
Davi Arnaut
if the socket structure is being cast back to the right type.
[21 Oct 2010 15:34]
Sveta Smirnova
Thank you for the report. Verified as described.
Description: viosocket.c:1078: warning: dereferencing pointer ‘norm_addr’ does break strict- How to repeat: user@machine:~/mysql/5.5/vio$ ccache gcc -DHAVE_CONFIG_H -I. -I../include -I../include -I../include -g -DSAFE_MUTEX -Wall -Wextra -Wunused -Wwrite-strings -mtune=native -DUNIV_MUST_NOT_INLINE -DEXTRA_DEBUG -DFORCE_INIT_OF_VARS -DSAFE_MUTEX -O3 -DUNIV_LINUX -MT viosocket.o -MD -MP -MF .deps/viosocket.Tpo -c -o viosocket.o viosocket.c viosocket.c: In function ‘vio_get_normalized_ip_string’: viosocket.c:1078: warning: dereferencing pointer ‘norm_addr’ does break strict-aliasing rules viosocket.c:421: note: initialized from here Suggested fix: user@machine:~/mysql/7.0$ bzr diff === modified file 'vio/viosocket.c' --- vio/viosocket.c 2010-05-26 09:50:01 +0000 +++ vio/viosocket.c 2010-10-19 10:54:45 +0000 @@ -856,8 +856,11 @@ my_bool vio_get_normalized_ip_string(con char *ip_string, size_t ip_string_size) { - struct sockaddr_storage norm_addr_storage; - struct sockaddr *norm_addr= (struct sockaddr *) &norm_addr_storage; + union { + struct sockaddr_storage norm_addr_storage; + struct sockaddr _avoid_strict_alias_warning; + } tmp_addr; + struct sockaddr *norm_addr= (struct sockaddr *) &tmp_addr.norm_addr_storage; int norm_addr_length; int err_code;