add workaround for zlib with cygwin build (v2)

include/shared.h

@@ -62,6 +62,10 @@ bool hc_string_is_digit (const char *s);
 void hc_string_trim_trailing (char *s);
 void hc_string_trim_leading (char *s);
 
+#if defined (__CYGWIN__)
+int    _wopen(const char *path, int oflag, ...);
+#endif
+
 bool   hc_fopen    (HCFILE *fp, const char *path, char *mode);
 int    hc_fscanf   (HCFILE *fp, const char *format, void *ptr);
 int    hc_fprintf  (HCFILE *fp, const char *format, ...);

src/Makefile

@@ -178,12 +178,8 @@ endif
 
 ## because ZLIB
 ifeq ($(USE_SYSTEM_ZLIB),0)
-ifeq ($(UNAME),CYGWIN)
-CFLAGS_ZLIB             += -Wno-implicit-fallthrough -UWIDECHAR
-else
 CFLAGS_ZLIB             += -Wno-implicit-fallthrough
 endif
-endif
 
 ifeq ($(DEBUG),0)
 CFLAGS                  += -O2

src/shared.c

@@ -602,6 +602,18 @@ void hc_string_trim_trailing (char *s)
   s[new_len] = 0;
 }
 
+#if defined (__CYGWIN__)
+// workaround for zlib with cygwin build
+int _wopen(const char *path, int oflag, ...)
+{
+  va_list ap;
+  va_start (ap, oflag);
+  int r = open (path, oflag, ap);
+  va_end (ap);
+  return r;
+}
+#endif
+
 bool hc_fopen (HCFILE *fp, const char *path, char *mode)
 {
   unsigned char check[3] = { 0 };