Hi.
I was looking at the cause for a test failing.
It came down to ...
size_t n;
if (n < 0) {
// Code never reached as n is unsigned and cannot be negative.
}
I'm not a strong c developer, but from reading it seems that size_t is
always unsigned.
Using the windows compiler (and turning on all the warnings via /Wall
though /W4 should be enough), this warning reports as ...
xxx\yyy.c(nnn) : warning C4296: '>=' : expression is always false
I then ran a full build and extracted all the C4926 warnings.
main\network.c(1175) : warning C4296: '>=' : expression is always true
main\streams\filter.c(363) : warning C4296: '<' : expression is always false
main\streams\streams.c(921) : warning C4296: '>=' : expression is always true
ext\mysqlnd\mysqlnd.c(1006) : warning C4296: '>=' : expression is always true
ext\mysqlnd\mysqlnd.c(1031) : warning C4296: '>=' : expression is always true
ext\mysqlnd\mysqlnd_loaddata.c(215) : warning C4296: '<' : expression
is always false
ext\mysqlnd\mysqlnd_loaddata.c(223) : warning C4296: '<' : expression
is always false
ext\mysqlnd\mysqlnd_ps.c(1480) : warning C4296: '<' : expression is always false
ext\mysqlnd\mysqlnd_ps.c(1620) : warning C4296: '<' : expression is always false
ext\standard\ftp_fopen_wrapper.c(645) : warning C4296: '>=' :
expression is always true
ext\standard\image.c(645) : warning C4296: '<' : expression is always false
ext\standard\streamsfuncs.c(637) : warning C4296: '>=' : expression is
always true
ext\standard\streamsfuncs.c(677) : warning C4296: '>=' : expression is
always true
ext\standard\var.c(403) : warning C4296: '<' : expression is always false
ext\pdo\pdo_stmt.c(463) : warning C4296: '<' : expression is always false
ext\soap\php_encoding.c(2794) : warning C4296: '<' : expression is always false
In the case of the bug [1], the incorrect type comparison resulted in
the suppression of an error which cased the test to fail, leading me
here.
I think other comparisons in the above list are also suppressing
errors (I think mysqlnd will fail to report a loss of connection
during mysqlnd_handle_local_infile() for example).
Regards,
Richard.
[1] http://bugs.php.net/bug.php?id=49072
--
Richard Quadling
Twitter : EE : Zend
@RQuadling : e-e.com/M_248814.html : bit.ly/9O8vFY