diff --git a/com.oracle.truffle.r.native/fficall/src/truffle_common/Rinternals_truffle_common.h b/com.oracle.truffle.r.native/fficall/src/truffle_common/Rinternals_truffle_common.h
index a577016795e017afddcbdb8543cb49b2d3595e76..8460b04e7bb91e65626301f0eae6a2039cb2c2d3 100644
--- a/com.oracle.truffle.r.native/fficall/src/truffle_common/Rinternals_truffle_common.h
+++ b/com.oracle.truffle.r.native/fficall/src/truffle_common/Rinternals_truffle_common.h
@@ -475,12 +475,12 @@ void R_ProtectWithIndex(SEXP x, PROTECT_INDEX *y) {
 
 void R_Reprotect(SEXP x, PROTECT_INDEX y) {
     TRACE("%p %i", x, y);
-    return ((call_R_Reprotect) callbacks[R_Reprotect_x])(x, y);
+    ((call_R_Reprotect) callbacks[R_Reprotect_x])(x, y);
 }
 
 void Rf_unprotect_ptr(SEXP x) {
     TRACE1(x);
-    return ((call_Rf_unprotect_ptr) callbacks[Rf_unprotect_ptr_x])(x);
+    ((call_Rf_unprotect_ptr) callbacks[Rf_unprotect_ptr_x])(x);
 }
 
 void R_FlushConsole(void) {