As multiple targets are affected apparently, I believe at least
aarch64, arm, powerpc64le, s390{,x} and ia64,
I think we should have a middle-end predicate for this, so that if we need
to tweak it, we can do it in one spot.
2020-04-22 Jakub Jelinek <jakub@redhat.com>
PR target/94383
* calls.h (cxx17_empty_base_field_p): Declare.
* calls.c (cxx17_empty_base_field_p): Define.
+2020-04-22 Jakub Jelinek <jakub@redhat.com>
+
+ PR target/94383
+ * calls.h (cxx17_empty_base_field_p): Declare.
+ * calls.c (cxx17_empty_base_field_p): Define.
+
2020-04-22 Christophe Lyon <christophe.lyon@linaro.org>
* doc/sourcebuild.texi (arm_softfp_ok, arm_hard_ok): Document.
return targetm.calls.must_pass_in_stack (arg);
}
+/* Return true if FIELD is the C++17 empty base field that should
+ be ignored for ABI calling convention decisions in order to
+ maintain ABI compatibility between C++14 and earlier, which doesn't
+ add this FIELD to classes with empty bases, and C++17 and later
+ which does. */
+
+bool
+cxx17_empty_base_field_p (const_tree field)
+{
+ return (TREE_CODE (field) == FIELD_DECL
+ && DECL_ARTIFICIAL (field)
+ && RECORD_OR_UNION_TYPE_P (TREE_TYPE (field))
+ && DECL_SIZE (field)
+ && integer_zerop (DECL_SIZE (field))
+ && TYPE_SIZE (TREE_TYPE (field))
+ && !integer_zerop (TYPE_SIZE (TREE_TYPE (field))));
+}
+
/* Tell the garbage collector about GTY markers in this source file. */
#include "gt-calls.h"
extern void maybe_warn_nonstring_arg (tree, tree);
extern bool get_size_range (tree, tree[2], bool = false);
extern rtx rtx_for_static_chain (const_tree, bool);
+extern bool cxx17_empty_base_field_p (const_tree);
#endif // GCC_CALLS_H