Greatly speedup has_mate_threat()

[stockfish] / src / piece.cpp

diff --git a/src/piece.cpp b/src/piece.cpp
index 707c8c57dfae3d53ae3de96d44de1a40d53e91f4..40babba695165c8ac7630f1e9b0c0222746308ea 100644 (file)
--- a/src/piece.cpp
+++ b/src/piece.cpp
@@ -36,7 +36,7 @@
 static const char PieceChars[] = " pnbrqk";
 
 char piece_type_to_char(PieceType pt, bool upcase) {
-  return upcase? toupper(PieceChars[pt]) : PieceChars[pt];
+  return char(upcase? toupper(PieceChars[pt]) : PieceChars[pt]);
 }
 
 PieceType piece_type_from_char(char c) {