crc32.c was #including limits.h in order to find a four-byte integer
type. It was doing this even if Z_SOLO were defined, violating the
intent of Z_SOLO, which is to include no library headers and require
no library functions. Now crc32.c obeys the intent of Z_SOLO, but
with the downside that crc32() will be slower than when not compiled
with Z_SOLO. This can be remedied manually by typedefing u4 to a
known four-byte unsigned integer type, and #defining BYFOUR in
crc32.c.
#define local static
/* Find a four-byte integer type for crc32_little() and crc32_big(). */
+#ifdef Z_SOLO
+# define NOBYFOUR
+#endif
#ifndef NOBYFOUR
# ifdef STDC /* need ANSI C limits.h to determine sizes */
# include <limits.h>