--- src/runtime/sparc-assem.S.orig	2023-08-12 20:04:45.888191830 +0200
+++ src/runtime/sparc-assem.S	2023-08-12 20:06:13.974581473 +0200
@@ -32,6 +32,15 @@
 #define ST_FLUSH_WINDOWS 0x03
 	.seg    "text"
         .global call_into_lisp
+
+#ifdef  __arch64__
+        /* Mark global registers as being used here. */
+        /* Can't use reg_NAME alias here, throws compiler error */
+        /* saying that it wants the _actual_ register name. */
+        .register       %g2,#scratch  /* reg_NULL */
+        .register       %g3,#scratch  /* reg_CSP */
+#endif
+
 call_into_lisp:
         save    %sp, -FRAMESIZE, %sp