| Message ID | 20210419211742.288906-1-polacek@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: ICE with concept defined in function [PR97536] | expand |
On 4/19/21 5:17 PM, Marek Polacek wrote: > This is an ICE-on-invalid, but I keep seeing it when reducing code so > I'd like to fix it. We crash on > > template <typename> void forward() { > concept C = true; > } > > which breaks two requirements: > [temp.concept]/1: A concept is a template ... > [temp.concept]/3: A concept-definition shall inhabit a namespace scope. > > This patch adds a test that exercises broken code and fixes the ICE > by checking that a concept-definition is defined at namespace scope. > > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? OK. > gcc/cp/ChangeLog: > > PR c++/97536 > * decl.c (grokvardecl): Given an error when a concept is not defined > at namespace scope. > > gcc/testsuite/ChangeLog: > > PR c++/97536 > * g++.dg/concepts/diagnostic16.C: New test. > --- > gcc/cp/decl.c | 6 +++ > gcc/testsuite/g++.dg/concepts/diagnostic16.C | 45 ++++++++++++++++++++ > 2 files changed, 51 insertions(+) > create mode 100644 gcc/testsuite/g++.dg/concepts/diagnostic16.C > > diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c > index 942eb318f2c..b81de8ef934 100644 > --- a/gcc/cp/decl.c > +++ b/gcc/cp/decl.c > @@ -10365,6 +10365,12 @@ grokvardecl (tree type, > "a non-template variable cannot be %<concept%>"); > return NULL_TREE; > } > + else if (!at_namespace_scope_p ()) > + { > + error_at (declspecs->locations[ds_concept], > + "concept must be defined at namespace scope"); > + return NULL_TREE; > + } > else > DECL_DECLARED_CONCEPT_P (decl) = true; > if (!same_type_ignoring_top_level_qualifiers_p (type, boolean_type_node)) > diff --git a/gcc/testsuite/g++.dg/concepts/diagnostic16.C b/gcc/testsuite/g++.dg/concepts/diagnostic16.C > new file mode 100644 > index 00000000000..fcba535a876 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/concepts/diagnostic16.C > @@ -0,0 +1,45 @@ > +// PR c++/97536 > +// { dg-do compile { target concepts } } > + > +template<typename> > +concept C1 = true; > + > +concept C2 = true; // { dg-error "non-template variable cannot be .concept." } > +// { dg-error "concept definition syntax is" "" { target *-*-* } .-1 } > + > +template<typename> > +void fn1 () > +{ > + concept bar = true; // { dg-error "concept must be defined at namespace scope" } > +// { dg-error "concept definition syntax is" "" { target *-*-* } .-1 } > +} > + > +void fn2 () > +{ > + concept bar = true; // { dg-error "non-template variable cannot be .concept." } > +// { dg-error "concept definition syntax is" "" { target *-*-* } .-1 } > +} > + > +template<typename> > +void fn3 () > +{ > + template<typename> // { dg-error "template declaration cannot appear at block scope" } > + concept bar = true; > +} > + > +void fn4 () > +{ > + template<typename> // { dg-error "template declaration cannot appear at block scope" } > + concept bar = true; > +} > + > +void fn5 () > +{ > + C1 auto x = 42; > +} > + > +template<typename> > +void fn6 () > +{ > + C1 auto x = 42; > +} > > base-commit: 329d2f0df7d6d22c87ab3338b94caef68139cd58 >
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index 942eb318f2c..b81de8ef934 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -10365,6 +10365,12 @@ grokvardecl (tree type, "a non-template variable cannot be %<concept%>"); return NULL_TREE; } + else if (!at_namespace_scope_p ()) + { + error_at (declspecs->locations[ds_concept], + "concept must be defined at namespace scope"); + return NULL_TREE; + } else DECL_DECLARED_CONCEPT_P (decl) = true; if (!same_type_ignoring_top_level_qualifiers_p (type, boolean_type_node)) diff --git a/gcc/testsuite/g++.dg/concepts/diagnostic16.C b/gcc/testsuite/g++.dg/concepts/diagnostic16.C new file mode 100644 index 00000000000..fcba535a876 --- /dev/null +++ b/gcc/testsuite/g++.dg/concepts/diagnostic16.C @@ -0,0 +1,45 @@ +// PR c++/97536 +// { dg-do compile { target concepts } } + +template<typename> +concept C1 = true; + +concept C2 = true; // { dg-error "non-template variable cannot be .concept." } +// { dg-error "concept definition syntax is" "" { target *-*-* } .-1 } + +template<typename> +void fn1 () +{ + concept bar = true; // { dg-error "concept must be defined at namespace scope" } +// { dg-error "concept definition syntax is" "" { target *-*-* } .-1 } +} + +void fn2 () +{ + concept bar = true; // { dg-error "non-template variable cannot be .concept." } +// { dg-error "concept definition syntax is" "" { target *-*-* } .-1 } +} + +template<typename> +void fn3 () +{ + template<typename> // { dg-error "template declaration cannot appear at block scope" } + concept bar = true; +} + +void fn4 () +{ + template<typename> // { dg-error "template declaration cannot appear at block scope" } + concept bar = true; +} + +void fn5 () +{ + C1 auto x = 42; +} + +template<typename> +void fn6 () +{ + C1 auto x = 42; +}
This is an ICE-on-invalid, but I keep seeing it when reducing code so I'd like to fix it. We crash on template <typename> void forward() { concept C = true; } which breaks two requirements: [temp.concept]/1: A concept is a template ... [temp.concept]/3: A concept-definition shall inhabit a namespace scope. This patch adds a test that exercises broken code and fixes the ICE by checking that a concept-definition is defined at namespace scope. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? gcc/cp/ChangeLog: PR c++/97536 * decl.c (grokvardecl): Given an error when a concept is not defined at namespace scope. gcc/testsuite/ChangeLog: PR c++/97536 * g++.dg/concepts/diagnostic16.C: New test. --- gcc/cp/decl.c | 6 +++ gcc/testsuite/g++.dg/concepts/diagnostic16.C | 45 ++++++++++++++++++++ 2 files changed, 51 insertions(+) create mode 100644 gcc/testsuite/g++.dg/concepts/diagnostic16.C base-commit: 329d2f0df7d6d22c87ab3338b94caef68139cd58