From afc63084b41f3e0f102d6c4327a69bb1368b7d3b Mon Sep 17 00:00:00 2001
From: Jeff Bezanson <jeff.bezanson@gmail.com>
Date: Thu, 2 Jul 2015 17:21:00 -0400
Subject: [PATCH] fix #11982

disable widening entirely when specializing staged functions
---
 src/gf.c       | 4 ++--
 test/staged.jl | 7 +++++++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/gf.c b/src/gf.c
index 7bd1a0a3e9d65..09b2f703edd21 100644
--- a/src/gf.c
+++ b/src/gf.c
@@ -471,7 +471,7 @@ static jl_function_t *cache_method(jl_methtable_t *mt, jl_tupletype_t *type,
     for (i=0; i < np; i++) {
         jl_value_t *elt = jl_tparam(type,i);
         jl_value_t *decl_i = jl_nth_slot_type(decl,i);
-        if (jl_is_type_type(elt) && jl_is_tuple_type(jl_tparam0(elt)) &&
+        if (!isstaged && jl_is_type_type(elt) && jl_is_tuple_type(jl_tparam0(elt)) &&
             !(jl_subtype(decl_i, (jl_value_t*)jl_type_type, 0) && !is_kind(decl_i))) {
             jl_methlist_t *curr = mt->defs;
             int ok=1;
@@ -520,7 +520,7 @@ static jl_function_t *cache_method(jl_methtable_t *mt, jl_tupletype_t *type,
                 set_to_any = 1;
             }
         }
-        if (set_to_any) {
+        if (set_to_any || isstaged) {
         }
         else if (jl_is_type_type(elt) && jl_is_type_type(jl_tparam0(elt)) &&
                  // give up on specializing static parameters for Type{Type{Type{...}}}
diff --git a/test/staged.jl b/test/staged.jl
index 695013f0faa85..81aa6ba212790 100644
--- a/test/staged.jl
+++ b/test/staged.jl
@@ -128,3 +128,10 @@ f10502() = ()
 # One-line @generated functions
 @generated oneliner(x,y) = :($x, x, $y, y)
 @test oneliner(1, 2.) == (Int, 1, Float64, 2.)
+
+# issue #11982
+@generated function f11982(T)
+    string(T.parameters[1])
+end
+@test f11982(Float32) == "Float32"
+@test f11982(Int32) == "Int32"