Define only least required macros for LFS in config.h.

cmake/TestFileOffsetBits.c

@@ -0,0 +1,9 @@
+#include <sys/types.h>
+
+int main(int argc, char **argv)
+{
+  /* Cause a compile-time error if off_t is smaller than 64 bits */
+#define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
+  int off_t_is_large[ (LARGE_OFF_T % 2147483629 == 721 && LARGE_OFF_T % 2147483647 == 1) ? 1 : -1 ];  
+  return 0;
+}