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From: "colin at reactos dot org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug regression/42145] New: Incorrect "may be used uninitialized warning" for a very specific test case Date: Sun, 22 Nov 2009 14:42:00 -0000 [thread overview] Message-ID: <bug-42145-18346@http.gcc.gnu.org/bugzilla/> (raw) I'm compiling the attached test case with "gcc version 4.5.0 20091018 (experimental) [trunk revision 152966] (Ubuntu 20091018-0ubuntu1)". When using the command line "gcc -Wuninitialized -Os -o test test_gccbug.c", I'm getting the following incorrect warning: test_gccbug.c: In function 'main': test_gccbug.c:17:6: warning: 'ret' may be used uninitialized in this function Same happens with different builds of GCC 4.4.2, 4.4.1 and 4.3.4. No such warning occurs with builds of GCC 4.2.4 and 4.1.3. This problem does not occur if one or more of the following is done: - You change the optimization level to -O0 or -O1 (-O2 and -O3 still trigger the bug in this GCC 4.5.0 version, but not always in older versions I've tested) - You comment out line 10 of the test case - You change line 22 of the test case to just 'if (!argc)' -- Summary: Incorrect "may be used uninitialized warning" for a very specific test case Product: gcc Version: 4.5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: regression AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: colin at reactos dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42145
next reply other threads:[~2009-11-22 14:42 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2009-11-22 14:42 colin at reactos dot org [this message] 2009-11-22 14:44 ` [Bug regression/42145] " colin at reactos dot org 2009-11-22 14:44 ` colin at reactos dot org 2009-12-30 16:59 ` manu at gcc dot gnu dot org
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