gcc/SOURCES/gcc8-rh1960701.patch
2021-11-09 09:54:35 +00:00

65 lines
2.4 KiB
Diff

--- gcc/cp/call.c
+++ gcc/cp/call.c
@@ -6904,7 +6904,7 @@ convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
elttype = cp_build_qualified_type
(elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
array = build_array_of_n_type (elttype, len);
- array = finish_compound_literal (array, new_ctor, complain, fcl_c99);
+ array = finish_compound_literal (array, new_ctor, complain);
/* Take the address explicitly rather than via decay_conversion
to avoid the error about taking the address of a temporary. */
array = cp_build_addr_expr (array, complain);
@@ -10984,13 +10984,11 @@ set_up_extended_ref_temp (tree decl, tree expr, vec<tree, va_gc> **cleanups,
lvalue-rvalue conversion applied to "a glvalue of literal type
that refers to a non-volatile temporary object initialized
with a constant expression". Rather than try to communicate
- that this VAR_DECL is a temporary, just mark it constexpr.
-
- Currently this is only useful for initializer_list temporaries,
- since reference vars can't appear in constant expressions. */
+ that this VAR_DECL is a temporary, just mark it constexpr. */
DECL_DECLARED_CONSTEXPR_P (var) = true;
DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
TREE_CONSTANT (var) = true;
+ TREE_READONLY (var) = true;
}
DECL_INITIAL (var) = init;
init = NULL_TREE;
--- gcc/cp/tree.c
+++ gcc/cp/tree.c
@@ -442,6 +442,14 @@ build_target_expr (tree decl, tree value, tsubst_flags_t complain)
|| useless_type_conversion_p (TREE_TYPE (decl),
TREE_TYPE (value)));
+ /* Set TREE_READONLY for optimization, such as gimplify_init_constructor
+ moving a constant aggregate into .rodata. */
+ if (CP_TYPE_CONST_NON_VOLATILE_P (type)
+ && !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
+ && !VOID_TYPE_P (TREE_TYPE (value))
+ && reduced_constant_expression_p (value))
+ TREE_READONLY (decl) = true;
+
if (complain & tf_no_cleanup)
/* The caller is building a new-expr and does not need a cleanup. */
t = NULL_TREE;
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp1y/pr95226.C
@@ -0,0 +1,17 @@
+// PR c++/95226
+// { dg-do run { target c++14 } }
+
+#include <vector>
+
+struct T {
+ unsigned a;
+ float b {8.};
+};
+
+int main()
+{
+ T t = {1};
+ std::vector<T> tt = {{1}, {2}};
+ if (t.a != 1 || t.b != 8.0f || tt[0].a != 1 || tt[0].b != 8.0f || tt[1].a != 2 || tt[1].b != 8.0f)
+ __builtin_abort ();
+}