6 files changed, 46 insertions, 0 deletions
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 23f5d3a..fc7b6b9 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2018-03-28  Alexandre Oliva <aoliva@redhat.com>
 
+	PR c++/84973
+	* decl2.c (note_vague_linkage_fn): Don't defer uninstantiated
+	templates.
+
 	PR c++/84968
 	* tree.c (strip_typedefs_expr): Reject STATEMENT_LISTs.
 
diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index e522b9e..fa75374 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -739,6 +739,9 @@ check_classfn (tree ctype, tree function, tree template_parms)
 void
 note_vague_linkage_fn (tree decl)
 {
+  if (processing_template_decl)
+    return;
+
   DECL_DEFER_OUTPUT (decl) = 1;
   vec_safe_push (deferred_fns, decl);
 }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 929d4dd..252854e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2018-03-28  Alexandre Oliva <aoliva@redhat.com>
 
+	PR c++/84973
+	* g++.dg/template/pr84973.C: New.
+	* g++.dg/template/pr84973-2.C: New.
+	* g++.dg/template/pr84973-3.C: New.
+
 	PR c++/84968
 	* g++.dg/eh/pr84968.C: New.
 
diff --git a/gcc/testsuite/g++.dg/template/pr84973-2.C b/gcc/testsuite/g++.dg/template/pr84973-2.C
new file mode 100644
index 0000000..41c205a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/pr84973-2.C
@@ -0,0 +1,13 @@
+// { dg-do compile }
+
+template <int> void a() {
+  typedef struct {
+    void b() try { b; } catch (short) { // { dg-error "invalid use" }
+    }
+  } c;
+}
+
+int
+main() {
+  a<0>();
+}
diff --git a/gcc/testsuite/g++.dg/template/pr84973-3.C b/gcc/testsuite/g++.dg/template/pr84973-3.C
new file mode 100644
index 0000000..eeac214
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/pr84973-3.C
@@ -0,0 +1,13 @@
+// { dg-do link }
+
+template <int> void a() {
+  typedef struct {
+    void b() try { b(); } catch (short) {
+    }
+  } c;
+}
+
+int
+main() {
+  a<0>();
+}
diff --git a/gcc/testsuite/g++.dg/template/pr84973.C b/gcc/testsuite/g++.dg/template/pr84973.C
new file mode 100644
index 0000000..b3f7170
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/pr84973.C
@@ -0,0 +1,8 @@
+// { dg-do compile }
+
+template <int> void a() {
+  typedef struct {
+    void b() try { b; } catch (short) {
+    }
+  } c;
+}