From 4556c5b3157f496c73f7fcd25d103ad3e6ff1874 Mon Sep 17 00:00:00 2001 From: Jason Merrill Date: Wed, 6 Mar 2019 13:39:24 -0500 Subject: [PATCH] PR c++/89576 - if constexpr of lambda capture. Now that we're doing implicit lambda capture in templates, we see x here as the lambda capture. maybe_convert_cond was doing nothing in a template, so we never called mark_rvalue_use on x. As part of the broad move toward doing more processing of non-dependent expressions, let's do this conversion. * semantics.c (maybe_convert_cond): Do convert a non-dependent condition in a template. * typeck.c (condition_conversion): Handle being called in a template. From-SVN: r269433 --- gcc/cp/ChangeLog | 8 ++++++++ gcc/cp/semantics.c | 4 ++-- gcc/cp/typeck.c | 9 ++++----- gcc/testsuite/g++.dg/cpp1z/constexpr-if15.C | 2 +- gcc/testsuite/g++.dg/cpp1z/constexpr-if28.C | 11 +++++++++++ 5 files changed, 26 insertions(+), 8 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp1z/constexpr-if28.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index cfd86b250d7..a076fa9a255 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,11 @@ +2019-03-06 Jason Merrill + + PR c++/89576 - if constexpr of lambda capture. + * semantics.c (maybe_convert_cond): Do convert a non-dependent + condition in a template. + * typeck.c (condition_conversion): Handle being called in a + template. + 2019-03-06 Marek Polacek PR c++/87378 - bogus -Wredundant-move warning. diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c index c03e4ef247c..2573b77f6d6 100644 --- a/gcc/cp/semantics.c +++ b/gcc/cp/semantics.c @@ -646,10 +646,10 @@ maybe_convert_cond (tree cond) return NULL_TREE; /* Wait until we instantiate templates before doing conversion. */ - if (processing_template_decl) + if (type_dependent_expression_p (cond)) return cond; - if (warn_sequence_point) + if (warn_sequence_point && !processing_template_decl) verify_sequence_points (cond); /* Do the conversion. */ diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c index 43ff3d63abd..9ceb7af0022 100644 --- a/gcc/cp/typeck.c +++ b/gcc/cp/typeck.c @@ -5867,18 +5867,17 @@ cp_truthvalue_conversion (tree expr) return c_common_truthvalue_conversion (input_location, expr); } -/* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */ +/* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. This + is a low-level function; most callers should use maybe_convert_cond. */ tree condition_conversion (tree expr) { tree t; - /* Anything that might happen in a template should go through - maybe_convert_cond. */ - gcc_assert (!processing_template_decl); t = perform_implicit_conversion_flags (boolean_type_node, expr, tf_warning_or_error, LOOKUP_NORMAL); - t = fold_build_cleanup_point_expr (boolean_type_node, t); + if (!processing_template_decl) + t = fold_build_cleanup_point_expr (boolean_type_node, t); return t; } diff --git a/gcc/testsuite/g++.dg/cpp1z/constexpr-if15.C b/gcc/testsuite/g++.dg/cpp1z/constexpr-if15.C index 1dd8beab89c..49c7b7abb63 100644 --- a/gcc/testsuite/g++.dg/cpp1z/constexpr-if15.C +++ b/gcc/testsuite/g++.dg/cpp1z/constexpr-if15.C @@ -7,5 +7,5 @@ constexpr int foo (int) { return 2; } template void a() { - if constexpr(foo) { }; + if constexpr(foo) { }; // { dg-error "overloaded" } } diff --git a/gcc/testsuite/g++.dg/cpp1z/constexpr-if28.C b/gcc/testsuite/g++.dg/cpp1z/constexpr-if28.C new file mode 100644 index 00000000000..8bfde6c1bdb --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1z/constexpr-if28.C @@ -0,0 +1,11 @@ +// PR c++/89576 +// { dg-do compile { target c++17 } } + +template +void foo() +{ + constexpr int x = 0; + [&] { + if constexpr (x) {} + }; +} -- 2.30.2