| Message ID | 20191127234300.GE10088@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series |
|
| Related | show |
On 11/27/19 6:43 PM, Jakub Jelinek wrote: > Hi! > > While working on the PR92695 bug, I've noticed a weird warning, when > the testcase contained (pointless, but not invalid) constexpr specifier on > pure virtual function. constexpr implies DECL_DECLARED_INLINE_P and > we would note_vague_linkage_fn and later complain that the inline > function wasn't ever defined. > As can be seen in the testcase, for inline pure virtual we warn the same. > The specifiers don't make much sense, but Jonathan nor I could find anything > that would say that inline pure virtual or constexpr pure virtual is > invalid. clang++ accepts those without warnings too. > > Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for > trunk? OK. > 2019-11-27 Jakub Jelinek <jakub@redhat.com> > > PR c++/92695 > * decl2.c (mark_used): Don't call note_vague_linkage_fn for pure > virtual functions, even if they are declared inline. > > * g++.dg/warn/inline3.C: New test. > > --- gcc/cp/decl2.c.jj 2019-11-12 09:09:33.658814862 +0100 > +++ gcc/cp/decl2.c 2019-11-27 18:26:53.698018564 +0100 > @@ -5596,8 +5596,11 @@ mark_used (tree decl, tsubst_flags_t com > vec_safe_push (no_linkage_decls, decl); > } > > - if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) > - && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl)) > + if (TREE_CODE (decl) == FUNCTION_DECL > + && DECL_DECLARED_INLINE_P (decl) > + && !DECL_INITIAL (decl) > + && !DECL_ARTIFICIAL (decl) > + && !DECL_PURE_VIRTUAL_P (decl)) > /* Remember it, so we can check it was defined. */ > note_vague_linkage_fn (decl); > > --- gcc/testsuite/g++.dg/warn/inline3.C.jj 2019-11-27 18:13:46.685074239 +0100 > +++ gcc/testsuite/g++.dg/warn/inline3.C 2019-11-27 18:18:40.688577837 +0100 > @@ -0,0 +1,20 @@ > +struct S { > + inline virtual void foo () = 0; // { dg-bogus "used but never defined" } > +#if __cplusplus > 201703L > + constexpr virtual void bar () = 0; // { dg-bogus "used but never defined" "" { target c++2a } } > +#else > + inline virtual void bar () = 0; // { dg-bogus "used but never defined" "" { target c++17_down } } > +#endif > + S () {} > +}; > +struct T : public S { > + inline virtual void foo () {} > +#if __cplusplus > 201703L > + constexpr virtual void bar () {} > +#else > + inline virtual void bar () {} > +#endif > + T () {} > +}; > +T t; > +void foo (S *s) { s->foo (); s->bar (); } > > Jakub >
--- gcc/cp/decl2.c.jj 2019-11-12 09:09:33.658814862 +0100 +++ gcc/cp/decl2.c 2019-11-27 18:26:53.698018564 +0100 @@ -5596,8 +5596,11 @@ mark_used (tree decl, tsubst_flags_t com vec_safe_push (no_linkage_decls, decl); } - if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) - && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl)) + if (TREE_CODE (decl) == FUNCTION_DECL + && DECL_DECLARED_INLINE_P (decl) + && !DECL_INITIAL (decl) + && !DECL_ARTIFICIAL (decl) + && !DECL_PURE_VIRTUAL_P (decl)) /* Remember it, so we can check it was defined. */ note_vague_linkage_fn (decl); --- gcc/testsuite/g++.dg/warn/inline3.C.jj 2019-11-27 18:13:46.685074239 +0100 +++ gcc/testsuite/g++.dg/warn/inline3.C 2019-11-27 18:18:40.688577837 +0100 @@ -0,0 +1,20 @@ +struct S { + inline virtual void foo () = 0; // { dg-bogus "used but never defined" } +#if __cplusplus > 201703L + constexpr virtual void bar () = 0; // { dg-bogus "used but never defined" "" { target c++2a } } +#else + inline virtual void bar () = 0; // { dg-bogus "used but never defined" "" { target c++17_down } } +#endif + S () {} +}; +struct T : public S { + inline virtual void foo () {} +#if __cplusplus > 201703L + constexpr virtual void bar () {} +#else + inline virtual void bar () {} +#endif + T () {} +}; +T t; +void foo (S *s) { s->foo (); s->bar (); }