Several missing warnings

gcc gives 5 warnings but clang gives none.

$ cat test.c
int main( void )
    unsigned x, y;
    if ( x == -1 ) x = x/0;
    x = x++;
    return 0;
$ clang test.c -O1 -Wsign-compare -Wuninitialized -Wunused -Wsequence-
$ clang --version
clang version 1.0 ( 76360)
Target: i386-apple-darwin9
Thread model: posix
$ gcc test.c -O1 -Wsign-compare -Wuninitialized -Wunused -Wsequence-
test.c: In function 'main':
test.c:4: warning: comparison between signed and unsigned
test.c:4: warning: division by zero
test.c:5: warning: operation on 'x' may be undefined
test.c:3: warning: unused variable 'y'
test.c:4: warning: 'x' is used uninitialized in this function

Bugzilla filed:

Robert P.

In March, I was told to use --analyze command. This was so by design. May be things have changed since then.

~/clang-test-> clang --analyze test.c -o test
test.c:5:5: warning: Value stored to 'x' is never read
     x = x++;
     ^ ~~~
test.c:5:9: warning: Value stored to 'x' is never read
     x = x++;
test.c:4:5: warning: Branch condition evaluates to an uninitialized value.
     if ( x == -1 ) x = x/0;
     ^ ~
3 diagnostics generated.