| Message ID | 20170210155504.GP13736@redhat.com |
|---|---|
| State | New |
| Headers | show |
OK. On Fri, Feb 10, 2017 at 10:55 AM, Marek Polacek <polacek@redhat.com> wrote: > This PR complains about -Wint-in-bool-context warning where it shouldn't. > Here, in "f<1 * 1>()" the MULT_EXPR isn't really in a boolean context, but we > warn anyway during overload resolution, when adding various template > candidates. I believe the way to prevent this is to honor complain & > tf_warning which is what this patch does. Does that seem reasonable or > is there a better way? > > Bootstrapped/regtested on x86_64-linux, ok for trunk? > > 2017-02-10 Marek Polacek <polacek@redhat.com> > > PR c++/79184 > * cvt.c (ocp_convert): Add a sentinel against -Wint-in-bool-context > if warnings shouldn't be given. > > * g++.dg/warn/Wint-in-bool-context-1.C: New. > > diff --git gcc/cp/cvt.c gcc/cp/cvt.c > index ae9991a..5f4b5e3 100644 > --- gcc/cp/cvt.c > +++ gcc/cp/cvt.c > @@ -798,7 +798,15 @@ ocp_convert (tree type, tree expr, int convtype, int flags, > to the underlying type first. */ > if (SCOPED_ENUM_P (intype) && (convtype & CONV_STATIC)) > e = build_nop (ENUM_UNDERLYING_TYPE (intype), e); > - return cp_truthvalue_conversion (e); > + if (complain & tf_warning) > + return cp_truthvalue_conversion (e); > + else > + { > + /* Prevent bogus -Wint-in-bool-context warnings coming > + from c_common_truthvalue_conversion down the line. */ > + warning_sentinel w (warn_int_in_bool_context); > + return cp_truthvalue_conversion (e); > + } > } > > converted = convert_to_integer_maybe_fold (type, e, dofold); > diff --git gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C > index e69de29..117eca4 100644 > --- gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C > +++ gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C > @@ -0,0 +1,16 @@ > +// PR c++/79184 > +// { dg-do compile } > +// { dg-options "-Wint-in-bool-context" } > + > +enum { E = 2 }; > +template <bool> void f(int) { } > +template <int> void f() {} > + > +int > +main () > +{ > + f<1 * 1>(); // { dg-bogus "in boolean context" } > + f<1 << 1>(); // { dg-bogus "in boolean context" } > + f<1 ? 3 : 2>(); // { dg-bogus "in boolean context" } > + f<E>(); // { dg-bogus "in boolean context" } > +} > > Marek
diff --git gcc/cp/cvt.c gcc/cp/cvt.c index ae9991a..5f4b5e3 100644 --- gcc/cp/cvt.c +++ gcc/cp/cvt.c @@ -798,7 +798,15 @@ ocp_convert (tree type, tree expr, int convtype, int flags, to the underlying type first. */ if (SCOPED_ENUM_P (intype) && (convtype & CONV_STATIC)) e = build_nop (ENUM_UNDERLYING_TYPE (intype), e); - return cp_truthvalue_conversion (e); + if (complain & tf_warning) + return cp_truthvalue_conversion (e); + else + { + /* Prevent bogus -Wint-in-bool-context warnings coming + from c_common_truthvalue_conversion down the line. */ + warning_sentinel w (warn_int_in_bool_context); + return cp_truthvalue_conversion (e); + } } converted = convert_to_integer_maybe_fold (type, e, dofold); diff --git gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C index e69de29..117eca4 100644 --- gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C +++ gcc/testsuite/g++.dg/warn/Wint-in-bool-context-1.C @@ -0,0 +1,16 @@ +// PR c++/79184 +// { dg-do compile } +// { dg-options "-Wint-in-bool-context" } + +enum { E = 2 }; +template <bool> void f(int) { } +template <int> void f() {} + +int +main () +{ + f<1 * 1>(); // { dg-bogus "in boolean context" } + f<1 << 1>(); // { dg-bogus "in boolean context" } + f<1 ? 3 : 2>(); // { dg-bogus "in boolean context" } + f<E>(); // { dg-bogus "in boolean context" } +}