diff --git a/src/gallium/drivers/r300/compiler/radeon_program.h b/src/gallium/drivers/r300/compiler/radeon_program.h
index 67be1b9f213..41af9815f80 100644
--- a/src/gallium/drivers/r300/compiler/radeon_program.h
+++ b/src/gallium/drivers/r300/compiler/radeon_program.h
@@ -42,7 +42,7 @@ struct rc_src_register {
 	unsigned int File:4;
 
 	/** Negative values may be used for relative addressing. */
-	signed int Index:(RC_REGISTER_INDEX_BITS+1);
+	unsigned int Index:RC_REGISTER_INDEX_BITS;
 	unsigned int RelAddr:1;
 
 	unsigned int Swizzle:12;