Support a special const-value refcount, use it for const strings.

1 files changed, 9 insertions, 3 deletions

diff --git a/src/rt/rust_builtin.cpp b/src/rt/rust_builtin.cpp
index d221e6e587b..cb16fbf067d 100644
--- a/src/rt/rust_builtin.cpp
+++ b/src/rt/rust_builtin.cpp
@@ -61,8 +61,12 @@ align_of(rust_task *task, type_desc *t) {
   return t->align;
 }
 
-extern "C" CDECL size_t
-refcount(rust_task *task, type_desc *t, size_t *v) {
+extern "C" CDECL intptr_t
+refcount(rust_task *task, type_desc *t, intptr_t *v) {
+
+    if (*v == CONST_REFCOUNT)
+        return CONST_REFCOUNT;
+
     // Passed-in value has refcount 1 too high
     // because it was ref'ed while making the call.
     return (*v) - 1;
@@ -277,7 +281,9 @@ debug_box(rust_task *task, type_desc *t, rust_box *box)
     task->log(rust_log::STDLIB, "debug_box(0x%" PRIxPTR ")", box);
     debug_tydesc_helper(task, t);
     task->log(rust_log::STDLIB, "  refcount %" PRIdPTR,
-              box->ref_count - 1);  // -1 because we ref'ed for this call
+              box->ref_count == CONST_REFCOUNT
+              ? CONST_REFCOUNT
+              : box->ref_count - 1);  // -1 because we ref'ed for this call
     for (uintptr_t i = 0; i < t->size; ++i) {
         task->log(rust_log::STDLIB,
                   "  byte %" PRIdPTR ": 0x%" PRIx8, i, box->data[i]);