Just for kicks, I pulled a copy of SVN trunk today, built it, and tried
compiling some existing code. While it caught a number of problems that
previous versions did not, it also reported a couple of cases that seem
spurious. Here's a small example:
> #include <stdlib.h>
> #include <stdio.h>
>
> int main(int argc, char **argv)
> {
> switch (argc) {
> case 0:
> {
> char *foo = malloc(1);
> if (!foo)
> TEST_LABEL:
> {
> printf("test\n");
> return 0;
> }
> free(foo);
> break;
> }
> case 1:
> {
> char *foo = "xyz";
> if (argv[0]) {
> goto TEST_LABEL;
> }
> printf(foo);
> break;
> }
> }
> return 0;
> }
Compiling this as follows:
> $ ~/gcc-trunk/bin/gcc -o test test.c -Wall
> test.c: In function ‘main’:
> test.c:23:4: warning: jump skips variable initialization
> test.c:11:2: note: label ‘TEST_LABEL’ defined here
> test.c:9:9: note: ‘foo’ declared here
While this warning is completely accurate, it's also spurious, because
the code that will execute after the jump to TEST_LABEL does not
reference the local variable 'foo' in the target block at all.
Now, I don't expect anyone to like this code... I've already fixed it up
to not be so horrifically bad, but it's still perfectly valid and should
not generate such a warning. Comments?
--
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
skype: kpfleming | jabber: kpfleming@xxxxxxxxxx
Check us out at www.digium.com & www.asterisk.org
