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From: "zackw at panix dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/37591] New: suppress "signed and unsigned" warnings when signed value known to be positive Date: Fri, 19 Sep 2008 18:13:00 -0000 [thread overview] Message-ID: <bug-37591-37@http.gcc.gnu.org/bugzilla/> (raw) In a case such as this, GCC ought to be able to prove that the signed variable is positive and therefore suppress "signed and unsigned" warnings. I see this in both C and C++. #define MAX(a,b) ((a) > (b) ? (a) : (b)) #define MIN(a,b) ((a) < (b) ? (a) : (b)) unsigned int constrain(unsigned int index, unsigned int offset, unsigned int limit) { int adj = index - offset; adj = MAX(adj, 0); return MIN(adj, limit); /* { dg-bogus "signed and unsigned" } */ } -- Summary: suppress "signed and unsigned" warnings when signed value known to be positive Product: gcc Version: 4.3.2 Status: UNCONFIRMED Keywords: diagnostic Severity: enhancement Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: zackw at panix dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37591
next reply other threads:[~2008-09-19 18:13 UTC|newest] Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top 2008-09-19 18:13 zackw at panix dot com [this message] 2008-09-19 20:56 ` [Bug c/37591] " pinskia at gcc dot gnu dot org 2008-09-19 21:29 ` zackw at panix dot com 2008-09-20 9:11 ` rguenth at gcc dot gnu dot org 2008-09-22 13:29 ` manu at gcc dot gnu dot org 2008-09-22 15:47 ` zackw at panix dot com 2008-09-22 16:44 ` manu at gcc dot gnu dot org
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