diff -r 611332453da0 -r 4eda5df55f86 src/chess/king.c
--- a/src/chess/king.c	Wed Aug 29 13:45:13 2018 +0200
+++ b/src/chess/king.c	Wed Aug 29 13:55:18 2018 +0200
@@ -70,10 +70,10 @@
     
     uint8_t opponent_color = opponent_color(move->piece&COLOR_MASK);
     
-    // being in check does not "block" the king, so don't test it here
+    /* being in check does not "block" the king, so don't test it here */
     _Bool blocked = 0;
     
-    // just test, if castling move is blocked
+    /* just test, if castling move is blocked */
     if (abs(move->tofile - move->fromfile) == 2) {
         if (move->tofile == fileidx('c')) {
             blocked |= gamestate->board[move->torow][fileidx('b')];