Re: changing "configure" to default to "gcc -g -O2 -fwrapv ..."

2006-12-31 Thread Zdenek Dvorak
Hello, > >I have been looking into infer_loop_bounds_from_signedness() called > >from infer_loop_bounds_from_undefined(). > >At some places, nowrap_type_p() is used but this function operates > >only on types, so there will be too many false positive there; yet we > >will miss warning through that

Re: GCC optimizes integer overflow: bug or feature?

2006-12-20 Thread Zdenek Dvorak
Hello, > > Paul Brook wrote: > > >> Compiler can optimize it any way it wants, > > >> as long as result is the same as unoptimized one. > > > > > > We have an option for that. It's called -O0. > > > > > > Pretty much all optimization will change the behavior of your program. > > > > Now that's

Re: GCC optimizes integer overflow: bug or feature?

2006-12-19 Thread Zdenek Dvorak
Hello, > >Now, if your argument is that following the LIA-1 standard will prevent > >optimizations that could otherwise be made if one followed only the C > >standard, that's a reasonable argument, but it should not be couched as > >if it implies that preventing the optimizations would not be f