[PR c++/84593] ice on braced init with uninit ref field

[Alexandre Oliva <aoliva@redhat.com>]

Don't allow the initializer expr to be NULL in a ctor initializer
list, make it error_marker_node instead.

Regstrapped on x86_64- and i686-linux-gnu.  Ok to install?

for  gcc/cp/ChangeLog

	PR c++/84593
	* typeck2.c (process_init_constructor_record): Set NULL next
	to error_marker_node.

for  gcc/testsuite/ChangeLog

	PR c++/84593
	* g++.dg/cpp1y/pr84593.C: New.
---
 gcc/cp/typeck2.c                     |    2 ++
 gcc/testsuite/g++.dg/cpp1y/pr84593.C |    8 ++++++++
 2 files changed, 10 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/cpp1y/pr84593.C

diff --git a/gcc/cp/typeck2.c b/gcc/cp/typeck2.c
index 153b46cca775..8c2aa3ed55a5 100644
--- a/gcc/cp/typeck2.c
+++ b/gcc/cp/typeck2.c
@@ -1529,6 +1529,8 @@ process_init_constructor_record (tree type, tree init, int nested,
       /* If this is a bitfield, now convert to the lowered type.  */
       if (type != TREE_TYPE (field))
 	next = cp_convert_and_check (TREE_TYPE (field), next, complain);
+      if (!next)
+	next = error_mark_node;
       flags |= picflag_from_initializer (next);
       CONSTRUCTOR_APPEND_ELT (v, field, next);
     }
diff --git a/gcc/testsuite/g++.dg/cpp1y/pr84593.C b/gcc/testsuite/g++.dg/cpp1y/pr84593.C
new file mode 100644
index 000000000000..8aa869f19193
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/pr84593.C
@@ -0,0 +1,8 @@
+// PR c++/84593
+// { dg-do compile { target c++14 } }
+
+struct a {
+  int x;
+  int c = 0;
+  int &b;
+} c = {}; // { dg-error "uninitialized reference" }

-- 
Alexandre Oliva, freedom fighter    http://FSFLA.org/~lxoliva/
You must be the change you wish to see in the world. -- Gandhi
Be Free! -- http://FSFLA.org/   FSF Latin America board member
Free Software Evangelist|Red Hat Brasil GNU Toolchain Engineer