diff --git a/libgloss/arm/crt0.S b/libgloss/arm/crt0.S
index 7c662f915..35c306be0 100644
--- a/libgloss/arm/crt0.S
+++ b/libgloss/arm/crt0.S
@@ -125,9 +125,11 @@
 
 	/* Set __heap_limit.  */
 	ldr     r1, [r0, #4]
+	cmp     r1, #0
+	beq     .LC33
 	ldr     r2, =__heap_limit
 	str     r1, [r2]
-
+.LC33:
 	ldr     r1, [r0, #0]
 	cmp     r1, #0
 	bne     .LC32