mesa: set input read only on success
diff --git a/src/mesa/shader/arbprogparse.c b/src/mesa/shader/arbprogparse.c
index d662e0b..b6b3c88 100644
--- a/src/mesa/shader/arbprogparse.c
+++ b/src/mesa/shader/arbprogparse.c
@@ -1576,8 +1576,9 @@
    if (err) {
       program_error(ctx, Program->Position, "Bad attribute binding");
    }
-
-   Program->Base.InputsRead |= (1 << *inputReg);
+   else {
+      Program->Base.InputsRead |= (1 << *inputReg);
+   }
 
    return err;
 }