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* [Bug c/21357] New: Erroneous warning: " ... may be used uninitialized in this function"
@ 2005-05-03 13:08 william at gallaf dot net
2005-05-03 13:33 ` [Bug c/21357] " william at gallaf dot net
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: william at gallaf dot net @ 2005-05-03 13:08 UTC (permalink / raw)
To: gcc-bugs
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Output of gcc -v:
Using built-in specs.
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-4.0.0/configure --prefix=/home/williamg/local/x86_64-40
--enable-__cxa_atexit --enable-languages=c,c++
Thread model: posix
gcc version 4.0.0
Command line:
~/local/x86_64-40/bin/gcc -O1 -Wall -Werror -c 3.c -o 3.o
Output:
cc1: warnings being treated as errors
3.c: In function âmainâ:
3.c:6: warning: âinitialised_when_a_is_non_zeroâ may be used uninitialized in
this function
Preprocessed source:
# 1 "3.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "3.c"
extern int g (int);
int main () {
const int a = g (0);
int initialised_when_a_is_non_zero;
if (a)
initialised_when_a_is_non_zero = 10;
g (1);
if (a)
g (initialised_when_a_is_non_zero);
return 0;
}
It's clearly impossible that we use initialised_when_a_is_non_zero unless it
has been initialised.
The warning does not appear with -O0.
Removing the line "g (1);" also makes the warning disappear.
--
Summary: Erroneous warning: " ... may be used uninitialized in
this function"
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: william at gallaf dot net
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: x86_64-unknown-linux-gnu
GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21357
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/21357] Erroneous warning: " ... may be used uninitialized in this function"
2005-05-03 13:08 [Bug c/21357] New: Erroneous warning: " ... may be used uninitialized in this function" william at gallaf dot net
@ 2005-05-03 13:33 ` william at gallaf dot net
2005-05-03 13:43 ` pinskia at gcc dot gnu dot org
2005-05-03 20:20 ` [Bug tree-optimization/21357] " jsm28 at gcc dot gnu dot org
2 siblings, 0 replies; 4+ messages in thread
From: william at gallaf dot net @ 2005-05-03 13:33 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From william at gallaf dot net 2005-05-03 13:32 -------
*** Bug 21358 has been marked as a duplicate of this bug. ***
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21357
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug c/21357] Erroneous warning: " ... may be used uninitialized in this function"
2005-05-03 13:08 [Bug c/21357] New: Erroneous warning: " ... may be used uninitialized in this function" william at gallaf dot net
2005-05-03 13:33 ` [Bug c/21357] " william at gallaf dot net
@ 2005-05-03 13:43 ` pinskia at gcc dot gnu dot org
2005-05-03 20:20 ` [Bug tree-optimization/21357] " jsm28 at gcc dot gnu dot org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-05-03 13:43 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-05-03 13:43 -------
This is known and a long standing bug.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21357
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/21357] Erroneous warning: " ... may be used uninitialized in this function"
2005-05-03 13:08 [Bug c/21357] New: Erroneous warning: " ... may be used uninitialized in this function" william at gallaf dot net
2005-05-03 13:33 ` [Bug c/21357] " william at gallaf dot net
2005-05-03 13:43 ` pinskia at gcc dot gnu dot org
@ 2005-05-03 20:20 ` jsm28 at gcc dot gnu dot org
2 siblings, 0 replies; 4+ messages in thread
From: jsm28 at gcc dot gnu dot org @ 2005-05-03 20:20 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From jsm28 at gcc dot gnu dot org 2005-05-03 20:20 -------
Not a C front end bug and previously reported more than once.
*** This bug has been marked as a duplicate of 5035 ***
--
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Component|c |tree-optimization
Resolution| |DUPLICATE
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21357
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2005-05-03 20:20 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2005-05-03 13:08 [Bug c/21357] New: Erroneous warning: " ... may be used uninitialized in this function" william at gallaf dot net
2005-05-03 13:33 ` [Bug c/21357] " william at gallaf dot net
2005-05-03 13:43 ` pinskia at gcc dot gnu dot org
2005-05-03 20:20 ` [Bug tree-optimization/21357] " jsm28 at gcc dot gnu dot org
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