diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc
index bcae1cbd973..0770cdcd768 100644
--- a/gcc/cp/constexpr.cc
+++ b/gcc/cp/constexpr.cc
@@ -7662,7 +7662,18 @@ cxx_eval_constant_expression (const constexpr_ctx *ctx, tree t,
 	  }
 
 	if (TREE_CODE (op) == PTRMEM_CST && !TYPE_PTRMEM_P (type))
-	  op = cplus_expand_constant (op);
+	  {
+	    op = cplus_expand_constant (op);
+	    if (TREE_CODE (op) == PTRMEM_CST)
+	      {
+		if (!ctx->quiet)
+		  error_at (loc, "%qE is not a constant expression when the "
+			    "class %qT is still incomplete", op,
+			    PTRMEM_CST_CLASS (op));
+		*non_constant_p = true;
+		return t;
+	      }
+	  }
 
 	if (TREE_CODE (op) == PTRMEM_CST && tcode == NOP_EXPR)
 	  {
diff --git a/gcc/testsuite/g++.dg/cpp0x/ptrmem-cst1.C b/gcc/testsuite/g++.dg/cpp0x/ptrmem-cst1.C
new file mode 100644
index 00000000000..0d6a6b6445d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/ptrmem-cst1.C
@@ -0,0 +1,11 @@
+// PR c++/107574
+// { dg-do compile { target c++11 } }
+
+struct A { int i; };
+struct B:A { int j; };
+struct C:B {
+  int k;
+  static_assert((int B::*) &C::k, ""); // { dg-error "non-constant|still incomplete" }
+};
+
+static_assert((int B::*) &C::k, "");