Re: [PATCH 0/4] bitpos expansion summary reloaded

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

On Sat, 29 Sep 2012 20:11:41 +0200, Jan Kratochvil wrote:
> On Sat, 29 Sep 2012 19:39:38 +0200, Jan Kratochvil wrote:
> > We need to either fix splint or (more likely) use a different tool, there are
> > too many cases missed this way.
> 
> clang-3.0+ (Fedora-17+) can do it:
> 
> $ clang -o t t.c -Wshorten-64-to-32
> t.c:5:14: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
>   reported = longvar;
>            ~ ^~~~~~~
> t.c:6:12: warning: implicit conversion loses integer precision: 'long' to 'int' [-Wshorten-64-to-32]
>   missed = longvar + a - b;
>          ~ ^~~~~~~~~~~~~~~
> 2 warnings generated.

Or gcc with -Wconversion:
t.c: In function ‘main’:
t.c:5:3: warning: conversion to ‘int’ from ‘long int’ may alter its value [-Wconversion]
t.c:6:24: warning: conversion to ‘int’ from ‘long int’ may alter its value [-Wconversion]

With gcc-4.8+ featuring the carets:
t.c: In function ‘main’:
t.c:5:3: warning: conversion to ‘int’ from ‘long int’ may alter its value [-Wconversion]
   reported = longvar;
   ^
t.c:6:24: warning: conversion to ‘int’ from ‘long int’ may alter its value [-Wconversion]
   missed = longvar + a - b;
                        ^

This way one can use --enable-targets=all currently incompatible with clang.


Jan