[Bug c/56523] -Wunitialized is described to be enabled by -Wall
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56523
--- Comment #1 from Paolo Carlini paolo.carlini at oracle dot com 2013-03-04
16:16:16 UTC ---
On which basis do you think it doesn't? In practice, for a stupid example like
the below, with -Wall:
int main()
{
int a;
return a;
}
I get:
test.c: In function ‘main’:
test.c:4:3: warning: ‘a’ is used uninitialized in this function
[-Wuninitialized]
[Bug c/56523] -Wunitialized is described to be enabled by -Wall
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56523
--- Comment #2 from corentinjabot at gmail dot com 2013-03-04 17:33:26 UTC ---
Actually after a few more test it works correctly but the statement This
enables some extra warning flags that are not enabled by -Wall. is confusing
since the to set of options overlap.
I also tested with the following c++ snippet:
#include iostream
class A {
public:
A() {}
bool foo;
void bar() {
if(foo)
std::cout Foo\n;
}
};
int main () {
A a;
a.bar();
return 0;
}
The uninitialized variable is detected only with -O1. It is vaguely documented
but that behavior seems quite odd and unexpected when you are not aware of it.
[Bug c/56523] -Wunitialized is described to be enabled by -Wall
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56523 Paolo Carlini paolo.carlini at oracle dot com changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution||WORKSFORME --- Comment #3 from Paolo Carlini paolo.carlini at oracle dot com 2013-03-04 17:43:18 UTC --- That some warnings are only emitted when optimizing is well known, and discussed in many places.
