diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 5196df9db4f..44c6b70abe6 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,10 @@
 2004-10-11  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/17936
+	* cp-tree.h (CLASSTYPE_TEMPLATE_SPECIALIZATION): Add a comment.
+	* pt.c (optimize_specialization_lookup_p): Do not optimize lookups
+	for members of partial or explicit specializations.
+
 	PR c++/17929
 	* decl2.c (finish_anon_union): Robustify.
 
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index 85d0aa6a791..6f777b195ef 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -2713,6 +2713,9 @@ struct lang_decl GTY(())
 
 #define DECL_TEMPLATE_SPECIALIZATION(NODE) (DECL_USE_TEMPLATE (NODE) == 2)
 #define SET_DECL_TEMPLATE_SPECIALIZATION(NODE) (DECL_USE_TEMPLATE (NODE) = 2)
+
+/* Returns true for an explicit or partial specialization of a class
+   template.  */
 #define CLASSTYPE_TEMPLATE_SPECIALIZATION(NODE) \
   (CLASSTYPE_USE_TEMPLATE (NODE) == 2)
 #define SET_CLASSTYPE_TEMPLATE_SPECIALIZATION(NODE) \
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index c794e35bf4e..36ff89b2679 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -774,6 +774,12 @@ optimize_specialization_lookup_p (tree tmpl)
 	  /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
 	     parameter.  */
 	  && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
+	  /* The optimized lookup depends on the fact that the
+	     template arguments for the member function template apply
+	     purely to the containing class, which is not true if the
+	     containing class is an explicit or partial
+	     specialization.  */
+	  && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
 	  && !DECL_MEMBER_TEMPLATE_P (tmpl)
 	  && !DECL_CONV_FN_P (tmpl)
 	  /* It is possible to have a template that is not a member
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 624e57ef301..ac5fa076e42 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2004-10-11  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/17936
+	* g++.dg/template/spec18.C: New test.
+
 2004-10-11  Steve Ellcey  <sje@cup.hp.com>
 
 	* testsuite/gcc.dg/ia64-asm-1.c: Add prototype for abort
diff --git a/gcc/testsuite/g++.dg/template/spec18.C b/gcc/testsuite/g++.dg/template/spec18.C
new file mode 100644
index 00000000000..a22e8543d0e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/spec18.C
@@ -0,0 +1,13 @@
+// PR c++/17936
+
+template<int, int N> struct A
+{
+  void foo();
+};
+
+template<int N> struct A<1, N>
+{
+  void foo();
+};
+
+template<> void A<1, 2>::foo();