From 9931a2bf8c807326be1596dc0698872e32823e17 Mon Sep 17 00:00:00 2001 From: Jason Merrill Date: Mon, 21 Feb 2011 10:35:44 -0500 Subject: re PR c++/47207 ([C++0x] ICE: in decl_constant_var_p, at cp/decl2.c:3563 on invalid code) PR c++/47207 * decl2.c (decl_constant_var_p): A constexpr var needs an initializer to be constant. * semantics.c (cxx_eval_constant_expression): Complain about constexpr var used in its own initializer. * call.c (set_up_extended_ref_temp): Set DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P too. From-SVN: r170365 --- gcc/cp/ChangeLog | 10 ++++++++++ gcc/cp/call.c | 1 + gcc/cp/decl2.c | 13 +++++++------ gcc/cp/semantics.c | 5 ++++- gcc/testsuite/ChangeLog | 4 ++++ gcc/testsuite/g++.dg/cpp0x/constexpr-diag2.C | 5 +++++ 6 files changed, 31 insertions(+), 7 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-diag2.C (limited to 'gcc') diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 9fde00c..208bb8c 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,13 @@ +2011-02-21 Jason Merrill + + PR c++/47207 + * decl2.c (decl_constant_var_p): A constexpr var needs an + initializer to be constant. + * semantics.c (cxx_eval_constant_expression): Complain about + constexpr var used in its own initializer. + * call.c (set_up_extended_ref_temp): Set + DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P too. + 2011-02-20 Jason Merrill PR c++/47199 diff --git a/gcc/cp/call.c b/gcc/cp/call.c index 078542a..8dccbbe 100644 --- a/gcc/cp/call.c +++ b/gcc/cp/call.c @@ -8149,6 +8149,7 @@ set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp) Currently this is only useful for initializer_list temporaries, since reference vars can't appear in constant expressions. */ DECL_DECLARED_CONSTEXPR_P (var) = true; + DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true; TREE_CONSTANT (var) = true; } DECL_INITIAL (var) = init; diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c index a4b7dfa9..93d44a4 100644 --- a/gcc/cp/decl2.c +++ b/gcc/cp/decl2.c @@ -3550,20 +3550,21 @@ decl_constant_var_p (tree decl) tree type = TREE_TYPE (decl); if (TREE_CODE (decl) != VAR_DECL) return false; - if (DECL_DECLARED_CONSTEXPR_P (decl)) - ret = true; - else if (CP_TYPE_CONST_NON_VOLATILE_P (type) - && INTEGRAL_OR_ENUMERATION_TYPE_P (type)) + if (DECL_DECLARED_CONSTEXPR_P (decl) + || (CP_TYPE_CONST_NON_VOLATILE_P (type) + && INTEGRAL_OR_ENUMERATION_TYPE_P (type))) { /* We don't know if a template static data member is initialized with - a constant expression until we instantiate its initializer. */ + a constant expression until we instantiate its initializer. Even + in the case of a constexpr variable, we can't treat it as a + constant until its initializer is complete in case it's used in + its own initializer. */ mark_used (decl); ret = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl); } else ret = false; - gcc_assert (!ret || DECL_INITIAL (decl)); return ret; } diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c index b7ed525..6a9c6a0 100644 --- a/gcc/cp/semantics.c +++ b/gcc/cp/semantics.c @@ -6768,7 +6768,10 @@ cxx_eval_constant_expression (const constexpr_call *call, tree t, tree type = TREE_TYPE (r); error ("the value of %qD is not usable in a constant " "expression", r); - if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) + 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), diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 77b0bef..3c989f8 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2011-02-21 Jason Merrill + + * g++.dg/cpp0x/constexpr-diag2.C: New. + 2011-02-20 Jason Merrill * g++.dg/cpp0x/constexpr-ctor7.C: New. diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-diag2.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-diag2.C new file mode 100644 index 0000000..c78416e --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-diag2.C @@ -0,0 +1,5 @@ +// PR c++/47207 +// { dg-options -std=c++0x } + +constexpr int X (X); // { dg-error "not usable" } +// { dg-message "own initializer" "" { target *-*-* } 4 } -- cgit v1.1