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| author | Marek Polacek <polacek@redhat.com> | 2019-06-22 14:43:00 +0000 |
|---|---|---|
| committer | Marek Polacek <mpolacek@gcc.gnu.org> | 2019-06-22 14:43:00 +0000 |
| commit | 7f3db013dc8264e39339ee4b83900ef25d0d32aa (patch) | |
| tree | 0c32ba3b5879f803ec2e6bce6acc515e16b044e3 /gcc | |
| parent | 4b3aa535793363636b0d2819908710fae5025723 (diff) | |
| download | gcc-7f3db013dc8264e39339ee4b83900ef25d0d32aa.zip gcc-7f3db013dc8264e39339ee4b83900ef25d0d32aa.tar.gz gcc-7f3db013dc8264e39339ee4b83900ef25d0d32aa.tar.bz2 | |
PR c++/90881 - bogus -Wunused-value in unevaluated context.
* cvt.c (convert_to_void): Don't emit unused warnings in
an unevaluated context.
* g++.dg/cpp0x/Wunused-value1.C: New test.
From-SVN: r272585
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cp/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/cp/cvt.c | 3 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/cpp0x/Wunused-value1.C | 20 |
4 files changed, 33 insertions, 1 deletions
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 93b4875..31336f9 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,9 @@ +2019-06-22 Marek Polacek <polacek@redhat.com> + + PR c++/90881 - bogus -Wunused-value in unevaluated context. + * cvt.c (convert_to_void): Don't emit unused warnings in + an unevaluated context. + 2019-06-22 Paolo Carlini <paolo.carlini@oracle.com> * decl.c (grokdeclarator): Use id_loc, typespec_loc, and diff --git a/gcc/cp/cvt.c b/gcc/cp/cvt.c index 1c405ec..23d2aab 100644 --- a/gcc/cp/cvt.c +++ b/gcc/cp/cvt.c @@ -1518,7 +1518,8 @@ convert_to_void (tree expr, impl_conv_void implicit, tsubst_flags_t complain) if (implicit != ICV_CAST && warn_unused_value && !TREE_NO_WARNING (expr) - && !processing_template_decl) + && !processing_template_decl + && !cp_unevaluated_operand) { /* The middle end does not warn about expressions that have been explicitly cast to void, so we must do so here. */ diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 80ea591..b0b1d4b 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2019-06-22 Marek Polacek <polacek@redhat.com> + + PR c++/90881 - bogus -Wunused-value in unevaluated context. + * g++.dg/cpp0x/Wunused-value1.C: New test. + 2019-06-22 Paolo Carlini <paolo.carlini@oracle.com> * g++.dg/diagnostic/auto-storage-1.C: New. diff --git a/gcc/testsuite/g++.dg/cpp0x/Wunused-value1.C b/gcc/testsuite/g++.dg/cpp0x/Wunused-value1.C new file mode 100644 index 0000000..a0683b6 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/Wunused-value1.C @@ -0,0 +1,20 @@ +// PR c++/90881 +// { dg-do compile { target c++11 } } +// { dg-options "-Wall" } + +namespace std { + struct true_type { static const bool value = true; }; + struct false_type { static const bool value = false; }; +} + +template <typename T, typename = void> struct status : std::false_type{}; + +template <typename T> struct status<T, decltype(T::member, void())> : std::true_type {}; // { dg-bogus "left operand of comma operator has no effect" } + +struct s1{int member;}; +struct s2{int _member;}; + +int main(){ + static_assert(status<s1>::value, "has member"); + static_assert(!status<s2>::value, "has no member"); +} |