Re: self-confidence of compiler

On May 8, 5:06 pm, Jon Skeet [C# MVP] <s...@xxxxxxxxx> wrote:
Peter Duniho <NpOeStPe...@xxxxxxxxxxxxxxxx> wrote:
<snip>
I do know that I don't recall my C++ code generating "this variable is
unassigned" errors, but that's probably due to the lack of *any* checking
as opposed to more correct checking.

I *seem* to remember that gcc had some checking like this, and
Microsoft's C compiler does with /Wall on, but it's not *hugely* smart
- it still complains at:

#include <stdio.h>

int main(void)
{
int x;
int y=1;
if (y==1)
{
x = 5;
}
printf ("%d", x);

}

Interestingly, the warning here talks about a "potentially
uninitialized local variable" - but if you remove the assignment in the
if statement, it turns the error into just "uninitialized local
variable".

<snip>
gcc, aCC (HP-UX), and Digital Mars all complain in some fashion about
uninitialized variables if you set the warning level high enough. I'd
have to do some tests as to what the exact messages are. I've had
issues in the dark past with static locals being used without being
initialized and the compiler not catching that.

Tim

.

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