MySQL Bugs: #29543: GCov information not written in case of crash

Bug #29543	GCov information not written in case of crash
Submitted:	4 Jul 2007 8:55	Modified:	7 Jul 2007 19:06
Reporter:	Kristian Nielsen	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Logging	Severity:	S3 (Non-critical)
Version:	5.0, 5.1	OS:	Any
Assigned to:	Kristian Nielsen	CPU Architecture:	Any

Description:
The BUILD/compile-pentium-gcov build script can be used to provide test coverage analysis using GCC and GCov.

A problem arises when the mysqld server crashes during tests. In this case, the server will exit before the information required by GCov can be written to disk. This causes GCov reports to be misleading.

How to repeat:
Run a test that crashes the mysqld server, and check gcov output afterwards.

Suggested fix:
In the write_core() function, call the GCC internal __gcov_flush() function just before crashing, to make sure coverage output is written.

I will submit a patch for this.

Pushed to mysql-5.0-engines and mysql-5.1-engines.

Pushed into 5.0.46

Pushed into 5.1.21-beta

Noted in 5.0.46, 5.1.21 changelogs.

gcov coverage-testing information was not written if the server crashed.

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/30483

ChangeSet@1.2519, 2007-07-07 07:46:17+02:00, knielsen@ymer.(none) +2 -0
  Bug #29543 GCov information not written in case of crash.
  
  For GCov builds, if the server crashes, the normal exit handler for writing
  coverage information is not executed due to the abnormal termination.
  
  Fix this by explicitly calling the __gcov_flush function in our crash handler.