| Message ID | AM4PR0701MB216293247895872E4B231064E4C20@AM4PR0701MB2162.eurprd07.prod.outlook.com |
|---|---|
| State | New |
| Headers | show |
On 10/03/2016 11:09 AM, Bernd Edlinger wrote: > Hi! > > This is a next step in extending the -Wint-in-bool-context warning > to cover the case when a conditional expression has only > one arm which evaluates to a non-boolean integer value. > > With a previous version of this warning, we found PR 77574, > among with several more or less false positives, but meanwhile, > mostly due to excluding conditional expressions that originate > from macro expansion, there are no false positives any more, > so I think this is fine now with -Wall. > > > Bootstrapped and reg-tested on x86_64-pc-linux-gnu. > Is it OK for trunk? > > > Thanks > Bernd. > > > patch-bool-context2.diff > > > c-family: > 2016-10-03 Bernd Edlinger <bernd.edlinger@hotmail.de> > > * c-common.c (c_common_truthvalue_conversion): Warn also for suspicious > conditional expression in boolean context when only one arm is > non-boolean. > > testsuite: > 2016-10-03 Bernd Edlinger <bernd.edlinger@hotmail.de> > > * c-c++-common/Wint-in-bool-context.c: Update test. OK. jeff
c-family: 2016-10-03 Bernd Edlinger <bernd.edlinger@hotmail.de> * c-common.c (c_common_truthvalue_conversion): Warn also for suspicious conditional expression in boolean context when only one arm is non-boolean. testsuite: 2016-10-03 Bernd Edlinger <bernd.edlinger@hotmail.de> * c-c++-common/Wint-in-bool-context.c: Update test. Index: gcc/c-family/c-common.c =================================================================== --- gcc/c-family/c-common.c (revision 240713) +++ gcc/c-family/c-common.c (working copy) @@ -4675,6 +4675,14 @@ c_common_truthvalue_conversion (location_t locatio warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context, "?: using integer constants in boolean context, " "the expression will always evaluate to %<true%>"); + else if ((TREE_CODE (val1) == INTEGER_CST + && !integer_zerop (val1) + && !integer_onep (val1)) + || (TREE_CODE (val2) == INTEGER_CST + && !integer_zerop (val2) + && !integer_onep (val2))) + warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context, + "?: using integer constants in boolean context"); } /* Distribute the conversion into the arms of a COND_EXPR. */ if (c_dialect_cxx ()) Index: gcc/testsuite/c-c++-common/Wint-in-bool-context.c =================================================================== --- gcc/testsuite/c-c++-common/Wint-in-bool-context.c (revision 240713) +++ gcc/testsuite/c-c++-common/Wint-in-bool-context.c (working copy) @@ -10,7 +10,7 @@ int foo (int a, int b) if (a > 0 && a <= (b == 2) ? 1 : 1) /* { dg-bogus "boolean context" } */ return 2; - if (a > 0 && a <= (b == 3) ? 0 : 2) /* { dg-bogus "boolean context" } */ + if (a > 0 && a <= (b == 3) ? 0 : 2) /* { dg-warning "boolean context" } */ return 3; if (a == b ? 0 : 0) /* { dg-bogus "boolean context" } */