------- Comment #3 from pinskia at gmail dot com 2008-09-21 16:36 ------- Subject: Re: New: Pointer arithmetic yields strange result
Sent from my iPhone On Sep 21, 2008, at 9:00 AM, "john dot spelis at 3dlabs dot com" <[EMAIL PROTECTED] > wrote: > An expression using ptr arithmetic yields an unusual result > unless a cast is applied; > The problematic expression; > MaxTimings = ((EDIDDetailed *) &pExt->checksum) - pDTD; That is a signed division while the below is unsigned. > > works only when cast as; > MaxTimings = (((uintptr_t) &pExt->checksum) - ((uintptr_t) > pDTD))/sizeof(*pDTD); > > This occurs on compilers back to 3.0.3 when testing on a x86. It's > also present > in a cross compiler built using 4.3.0 source > Works on a Sun/Solaris compiler. > A test program is attached > > > -- > Summary: Pointer arithmetic yields strange result > Product: gcc > Version: 4.3.0 > Status: UNCONFIRMED > Severity: normal > Priority: P3 > Component: c > AssignedTo: unassigned at gcc dot gnu dot org > ReportedBy: john dot spelis at 3dlabs dot com > GCC build triplet: i686-pc-linux-gnu > GCC host triplet: i686-pc-linux-gnu > GCC target triplet: i686-pc-linux-gnu > > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37609 > -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37609
