From: Jason Merrill Date: Sun, 27 Feb 2011 08:13:16 +0000 (-0500) Subject: re PR c++/47897 ([C++0x] static const member variable is not constant expression) X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=acfd3fffee80262c74de0e4480b983d7bf7fbd8e;p=gcc.git re PR c++/47897 ([C++0x] static const member variable is not constant expression) PR c++/47897 * semantics.c (non_const_var_error): Split out from... (cxx_eval_constant_expression): ...here. (potential_constant_expression_1) [VAR_DECL]: Use it. Allow dependent variables. From-SVN: r170532 --- diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 3dba66e335b..828336212b3 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,11 @@ +2011-02-26 Jason Merrill + + PR c++/47897 + * semantics.c (non_const_var_error): Split out from... + (cxx_eval_constant_expression): ...here. + (potential_constant_expression_1) [VAR_DECL]: Use it. + Allow dependent variables. + 2011-02-24 Jason Merrill * parser.c (cp_parser_constant_expression): Set diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c index 199084a6008..a33a7edd314 100644 --- a/gcc/cp/semantics.c +++ b/gcc/cp/semantics.c @@ -6704,6 +6704,46 @@ cxx_eval_indirect_ref (const constexpr_call *call, tree t, return r; } +/* Complain about R, a VAR_DECL, not being usable in a constant expression. + Shared between potential_constant_expression and + cxx_eval_constant_expression. */ + +static void +non_const_var_error (tree r) +{ + tree type = TREE_TYPE (r); + error ("the value of %qD is not usable in a constant " + "expression", r); + if (DECL_DECLARED_CONSTEXPR_P (r)) + inform (DECL_SOURCE_LOCATION (r), + "%qD used in its own initializer", r); + else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) + { + if (!CP_TYPE_CONST_P (type)) + inform (DECL_SOURCE_LOCATION (r), + "%q#D is not const", r); + else if (CP_TYPE_VOLATILE_P (type)) + inform (DECL_SOURCE_LOCATION (r), + "%q#D is volatile", r); + else if (!DECL_INITIAL (r)) + inform (DECL_SOURCE_LOCATION (r), + "%qD was not initialized with a constant " + "expression", r); + else + gcc_unreachable (); + } + else + { + if (cxx_dialect >= cxx0x && !DECL_DECLARED_CONSTEXPR_P (r)) + inform (DECL_SOURCE_LOCATION (r), + "%qD was not declared %", r); + else + inform (DECL_SOURCE_LOCATION (r), + "%qD does not have integral or enumeration type", + r); + } +} + /* Attempt to reduce the expression T to a constant value. On failure, issue diagnostic and return error_mark_node. */ /* FIXME unify with c_fully_fold */ @@ -6744,39 +6784,7 @@ cxx_eval_constant_expression (const constexpr_call *call, tree t, if (DECL_P (r)) { if (!allow_non_constant) - { - tree type = TREE_TYPE (r); - error ("the value of %qD is not usable in a constant " - "expression", r); - if (DECL_DECLARED_CONSTEXPR_P (r)) - inform (DECL_SOURCE_LOCATION (r), - "%qD used in its own initializer", r); - else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) - { - if (!CP_TYPE_CONST_P (type)) - inform (DECL_SOURCE_LOCATION (r), - "%q#D is not const", r); - else if (CP_TYPE_VOLATILE_P (type)) - inform (DECL_SOURCE_LOCATION (r), - "%q#D is volatile", r); - else if (!DECL_INITIAL (r)) - inform (DECL_SOURCE_LOCATION (r), - "%qD was not initialized with a constant " - "expression", r); - else - gcc_unreachable (); - } - else - { - if (cxx_dialect >= cxx0x && !DECL_DECLARED_CONSTEXPR_P (r)) - inform (DECL_SOURCE_LOCATION (r), - "%qD was not declared %", r); - else - inform (DECL_SOURCE_LOCATION (r), - "%qD does not have integral or enumeration type", - r); - } - } + non_const_var_error (r); *non_constant_p = true; } break; @@ -7371,10 +7379,11 @@ potential_constant_expression_1 (tree t, bool want_rval, tsubst_flags_t flags) return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval, flags); case VAR_DECL: - if (want_rval && !decl_constant_var_p (t)) + if (want_rval && !decl_constant_var_p (t) + && !dependent_type_p (TREE_TYPE (t))) { if (flags & tf_error) - error ("variable %qD is not declared constexpr", t); + non_const_var_error (t); return false; } return true; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 3cb2809056b..b23419a322c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,11 @@ +2011-02-26 Jason Merrill + + * g++.dg/cpp0x/regress/template-const1.C: New. + * g++.dg/cpp0x/regress/template-function1.C: Adjust. + * g++.dg/template/function1.C: Adjust. + * g++.dg/cpp0x/regress/debug-debug7.C: Adjust. + * g++.dg/debug/debug7.C: Adjust. + 2011-02-26 Tobias Burnus PR fortran/47886 diff --git a/gcc/testsuite/g++.dg/cpp0x/regress/debug-debug7.C b/gcc/testsuite/g++.dg/cpp0x/regress/debug-debug7.C index 8ee8824719d..ea8f1eb2e6c 100644 --- a/gcc/testsuite/g++.dg/cpp0x/regress/debug-debug7.C +++ b/gcc/testsuite/g++.dg/cpp0x/regress/debug-debug7.C @@ -7,8 +7,8 @@ int main() { int a = 4; - int b = 5; - int (*x)[b] = new int[a][b]; // { dg-error "" } + int b = 5; // { dg-message "not const" } + int (*x)[b] = new int[a][b]; // { dg-error "not usable" } x[2][1] = 7; diff --git a/gcc/testsuite/g++.dg/cpp0x/regress/template-const1.C b/gcc/testsuite/g++.dg/cpp0x/regress/template-const1.C new file mode 100644 index 00000000000..32db1f831b4 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/regress/template-const1.C @@ -0,0 +1,9 @@ +// PR c++/47897 +// { dg-options -std=c++0x } + +template < typename T, T N > +struct S +{ + static const T value = N; + typedef S< T, value + 1 > next; +}; diff --git a/gcc/testsuite/g++.dg/cpp0x/regress/template-function1.C b/gcc/testsuite/g++.dg/cpp0x/regress/template-function1.C index 028669e511e..66cbd4ba124 100644 --- a/gcc/testsuite/g++.dg/cpp0x/regress/template-function1.C +++ b/gcc/testsuite/g++.dg/cpp0x/regress/template-function1.C @@ -1,28 +1,29 @@ // PR c++/38647 // { dg-do compile } // { dg-options "-std=c++0x" } +// { dg-prune-output "note" } template struct A {}; const char func[] = "abc"; -template struct A {}; // { dg-error "cannot appear|is invalid|not a valid|not declared constexpr" } +template struct A {}; // { dg-error "cannot appear|is invalid|not a valid|constant expression" } char a1[1]; A a; template struct B {}; -template struct B<__FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|not declared constexpr" } +template struct B<__FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|constant expression" } char b1[1]; B b; template struct C {}; -template struct C<__PRETTY_FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|not declared constexpr" } +template struct C<__PRETTY_FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|constant expression" } char c1[1]; C c; template struct D {}; -template struct D<__func__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|function scope|not declared constexpr" } +template struct D<__func__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|function scope|constant expression" } char d1[1]; D d; diff --git a/gcc/testsuite/g++.dg/debug/debug7.C b/gcc/testsuite/g++.dg/debug/debug7.C index 31d47eda78f..8731cf81da7 100644 --- a/gcc/testsuite/g++.dg/debug/debug7.C +++ b/gcc/testsuite/g++.dg/debug/debug7.C @@ -1,4 +1,5 @@ // { dg-do compile } +// { dg-prune-output "note" } void f (int); diff --git a/gcc/testsuite/g++.dg/template/function1.C b/gcc/testsuite/g++.dg/template/function1.C index 8a112c1459f..bceed9d68f9 100644 --- a/gcc/testsuite/g++.dg/template/function1.C +++ b/gcc/testsuite/g++.dg/template/function1.C @@ -1,27 +1,28 @@ // PR c++/38647 // { dg-do compile } +// { dg-prune-output "note" } template struct A {}; const char func[] = "abc"; -template struct A {}; // { dg-error "cannot appear|is invalid|not a valid|not declared constexpr" } +template struct A {}; // { dg-error "cannot appear|is invalid|not a valid|constant expression" } char a1[1]; A a; template struct B {}; -template struct B<__FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|not declared constexpr" } +template struct B<__FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|constant expression" } char b1[1]; B b; template struct C {}; -template struct C<__PRETTY_FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|not declared constexpr" } +template struct C<__PRETTY_FUNCTION__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|constant expression" } char c1[1]; C c; template struct D {}; -template struct D<__func__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|function scope|not declared constexpr" } +template struct D<__func__, N> {}; // { dg-error "cannot appear|is invalid|is not a valid|function scope|constant expression" } char d1[1]; D d;