ensure binding type is set consistently for consts

Previously, `get_binding_type` would usually return `Any` for constants.
I think always setting it to the type of the actual value is probably
useful.

src/module.c

@@ -680,14 +680,13 @@ JL_DLLEXPORT void jl_set_const(jl_module_t *m JL_ROOTING_ARGUMENT, jl_sym_t *var
         uint8_t constp = 0;
         // if (jl_atomic_cmpswap(&bp->constp, &constp, 1)) {
         if (constp = bp->constp, bp->constp = 1, constp == 0) {
-            jl_value_t *old = NULL;
+            jl_value_t *old_ty = NULL, *old = NULL;
+            jl_atomic_cmpswap_relaxed(&bp->ty, &old_ty, jl_typeof(val));
             if (jl_atomic_cmpswap(&bp->value, &old, val)) {
                 jl_gc_wb_binding(bp, val);
                 return;
             }
         }
-	jl_value_t *old_ty = NULL;
-        jl_atomic_cmpswap_relaxed(&bp->ty, &old_ty, (jl_value_t*)jl_any_type);
     }
     jl_errorf("invalid redefinition of constant %s",
               jl_symbol_name(bp->name));
@@ -807,11 +806,8 @@ void jl_binding_deprecation_warning(jl_module_t *m, jl_binding_t *b)
 JL_DLLEXPORT void jl_checked_assignment(jl_binding_t *b, jl_value_t *rhs)
 {
     jl_value_t *old_ty = NULL;
-    if (!jl_atomic_cmpswap_relaxed(&b->ty, &old_ty, (jl_value_t*)jl_any_type) && !jl_isa(rhs, old_ty)) {
-        jl_errorf("cannot assign an incompatible value to the global %s.",
-                  jl_symbol_name(b->name));
-    }
     if (b->constp) {
+        jl_atomic_cmpswap_relaxed(&b->ty, &old_ty, jl_typeof(rhs));
         jl_value_t *old = NULL;
         if (jl_atomic_cmpswap(&b->value, &old, rhs)) {
             jl_gc_wb_binding(b, rhs);
@@ -828,6 +824,10 @@ JL_DLLEXPORT void jl_checked_assignment(jl_binding_t *b, jl_value_t *rhs)
         jl_safe_printf("WARNING: redefinition of constant %s. This may fail, cause incorrect answers, or produce other errors.\n",
                        jl_symbol_name(b->name));
     }
+    if (!jl_atomic_cmpswap_relaxed(&b->ty, &old_ty, (jl_value_t*)jl_any_type) && !jl_isa(rhs, old_ty)) {
+        jl_errorf("cannot assign an incompatible value to the global %s.",
+                  jl_symbol_name(b->name));
+    }
     jl_atomic_store_relaxed(&b->value, rhs);
     jl_gc_wb_binding(b, rhs);
 }

test/misc.jl

@@ -1109,3 +1109,6 @@ end
 @testset "Base/timing.jl" begin
     @test Base.jit_total_bytes() >= 0
 end
+
+const I_AM_A_CONSTANT_INT = 1
+@test Core.get_binding_type(@__MODULE__, :I_AM_A_CONSTANT_INT) == Int