Since in r265788 I made cxx_eval_outermost_constant_expr more insistent that the returned value have the right type, it became more important that initialized_type be correct. These two PRs were cases of it giving the wrong answer. On ARM, a constructor returns a pointer to the object, but initialized_type should return the class type, not that pointer type. And we need to look through COMPOUND_EXPR.
I tested that this fixes one of the affected testcases on ARM, and causes no regressions on x86_64-pc-linux-gnu. I haven't been able to get a cross toolchain to work properly; currently link tests are failing with undefined __sync_synchronize. Applying to trunk. PR c++/88293 - ICE with comma expression. * constexpr.c (initialized_type): Don't shortcut non-void type. Handle COMPOUND_EXPR. (cxx_eval_outermost_constant_expr): Return early for void type. --- gcc/cp/constexpr.c | 8 +++++--- gcc/testsuite/g++.dg/cpp0x/constexpr-comma1.C | 9 +++++++++ gcc/cp/ChangeLog | 8 ++++++++ 3 files changed, 22 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-comma1.C diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c index ed4bbeeb157..42681416760 100644 --- a/gcc/cp/constexpr.c +++ b/gcc/cp/constexpr.c @@ -2848,9 +2848,7 @@ initialized_type (tree t) if (TYPE_P (t)) return t; tree type = TREE_TYPE (t); - if (!VOID_TYPE_P (type)) - /* No need to look deeper. */; - else if (TREE_CODE (t) == CALL_EXPR) + if (TREE_CODE (t) == CALL_EXPR) { /* A constructor call has void type, so we need to look deeper. */ tree fn = get_function_named_in_call (t); @@ -2858,6 +2856,8 @@ initialized_type (tree t) && DECL_CXX_CONSTRUCTOR_P (fn)) type = DECL_CONTEXT (fn); } + else if (TREE_CODE (t) == COMPOUND_EXPR) + return initialized_type (TREE_OPERAND (t, 1)); else if (TREE_CODE (t) == AGGR_INIT_EXPR) type = TREE_TYPE (AGGR_INIT_EXPR_SLOT (t)); return cv_unqualified (type); @@ -5061,6 +5061,8 @@ cxx_eval_outermost_constant_expr (tree t, bool allow_non_constant, tree type = initialized_type (t); tree r = t; + if (VOID_TYPE_P (type)) + return t; if (AGGREGATE_TYPE_P (type) || VECTOR_TYPE_P (type)) { /* In C++14 an NSDMI can participate in aggregate initialization, diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-comma1.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-comma1.C new file mode 100644 index 00000000000..9dd1299ddf4 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-comma1.C @@ -0,0 +1,9 @@ +// PR c++/88293 +// { dg-do compile { target c++11 } } + +struct A +{ + constexpr A () { } +}; + +const A &a = (A (), A ()); diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 111782aeaba..20a54719578 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,11 @@ +2019-01-21 Jason Merrill <ja...@redhat.com> + + PR c++/87893 - constexpr ctor ICE on ARM. + PR c++/88293 - ICE with comma expression. + * constexpr.c (initialized_type): Don't shortcut non-void type. + Handle COMPOUND_EXPR. + (cxx_eval_outermost_constant_expr): Return early for void type. + 2019-01-21 Jakub Jelinek <ja...@redhat.com> PR c++/88949 base-commit: feb90a0dd6fc4e12786dce8338f716253d50b545 -- 2.20.1