PR c++/91845 - ICE with invalid pointer-to-member.

	* expr.c (mark_use): Use error_operand_p.
	* typeck2.c (build_m_component_ref): Check error_operand_p after
	calling mark_[lr]value_use.

	* g++.dg/cpp1y/pr91845.C: New test.

From-SVN: r276102

gcc/cp/ChangeLog

+2019-09-24  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/91845 - ICE with invalid pointer-to-member.
+	* expr.c (mark_use): Use error_operand_p.
+	* typeck2.c (build_m_component_ref): Check error_operand_p after
+	calling mark_[lr]value_use.
+
 2019-09-23  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	* pt.c (check_explicit_specialization): Use cp_expr_loc_or_input_loc.

gcc/cp/expr.c

@@ -96,7 +96,7 @@ mark_use (tree expr, bool rvalue_p, bool read_p,
 {
 #define RECUR(t) mark_use ((t), rvalue_p, read_p, loc, reject_builtin)
 
-  if (expr == NULL_TREE || expr == error_mark_node)
+  if (expr == NULL_TREE || error_operand_p (expr))
     return expr;
 
   if (reject_builtin && reject_gcc_builtin (expr, loc))

gcc/cp/typeck2.c

@@ -2068,12 +2068,12 @@ build_m_component_ref (tree datum, tree component, tsubst_flags_t complain)
   tree binfo;
   tree ctype;
 
-  if (error_operand_p (datum) || error_operand_p (component))
-    return error_mark_node;
-
   datum = mark_lvalue_use (datum);
   component = mark_rvalue_use (component);
 
+  if (error_operand_p (datum) || error_operand_p (component))
+    return error_mark_node;
+
   ptrmem_type = TREE_TYPE (component);
   if (!TYPE_PTRMEM_P (ptrmem_type))
     {

gcc/testsuite/ChangeLog

+2019-09-24  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/91845 - ICE with invalid pointer-to-member.
+	* g++.dg/cpp1y/pr91845.C: New test.
+
 2019-09-24  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* gcc.target/aarch64/nosplit-di-const-volatile_1.c: New test.

gcc/testsuite/g++.dg/cpp1y/pr91845.C

+// PR c++/91845 - ICE with invalid pointer-to-member.
+// { dg-do compile { target c++14 } }
+
+void non_const_mem_ptr() {
+  struct A {
+  };
+  constexpr A a = {1, 2}; // { dg-error "too many initializers" }
+  struct B {
+    int A::*p;
+    constexpr int g() const {
+      return a.*p; // { dg-error "use of local variable" }
+    };
+  };
+}