Merge pull request #1840 from ksss/bit-field

set bit field for mrb_bool

mrbgems/mruby-random/src/mt19937ar.h

@@ -15,7 +15,7 @@ typedef struct {
   };
 
   mrb_int seed;
-  mrb_bool has_seed;
+  mrb_bool has_seed : 1;
 } mt_state;
 
 void mrb_random_init_genrand(mt_state *, unsigned long);

src/string.c

@@ -41,7 +41,7 @@
 const char mrb_digitmap[] = "0123456789abcdefghijklmnopqrstuvwxyz";
 
 typedef struct mrb_shared_string {
-  mrb_bool nofree;
+  mrb_bool nofree : 1;
   int refcnt;
   char *ptr;
   mrb_int len;

src/symbol.c

@@ -12,7 +12,7 @@
 
 /* ------------------------------------------------------ */
 typedef struct symbol_name {
-  mrb_bool lit;
+  mrb_bool lit : 1;
   uint16_t len;
   const char *name;
 } symbol_name;