Fix a compilation error for MSVC

snicolet · snicolet · commit 9ca014df497d · 2018-07-27T15:46:13.000+02:00
The previous commit wouldn't compile on the Microsoft Virtual Studio C++ compiler. So use a more compatible style for the same idea (which we already use in numerous places of evaluate.cpp, for instance in line 563).

Under the Clang compiler, both versions generate exactly the same machine code (same md5 signatures for the two binaries).

No functional change.
diff --git a/src/evaluate.cpp b/src/evaluate.cpp
@@ -636,8 +636,8 @@ namespace {
 
         assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up)));
 
-        bb = forward_file_bb(Us, s) & pos.pieces(Them);
-        score -= HinderPassedPawn * bool(bb);
+        if (forward_file_bb(Us, s) & pos.pieces(Them))
+            score -= HinderPassedPawn;
 
         int r = relative_rank(Us, s);
         int w = PassedDanger[r];
