Re: Bison 3.5 - y.tab.c generates compiler warnings

On Wed, 18 Dec 2019, Paul Eggert wrote:

; On 12/18/19 10:22 PM, Akim Demaille wrote:
; > I was unable to reproduce that warning (https://travis-ci.org/akimd/bison/builds/626034753)
;
; I suspect you need a platform where plain 'char' is unsigned, so that 'typedef
; yytype_uint8 yy_state_t;' is treated as if it were 'typedef char yy_state_t;'
; which means yy_state_t indexes provoke the diagnostic. (A GCC bug, if you ask me.)

Given this in the template:

	#if defined __UINT_LEAST8_MAX__ && __UINT_LEAST8_MAX__ <= __INT_MAX__
	typedef __UINT_LEAST8_TYPE__ yytype_uint8;
	#elif (!defined __UINT_LEAST8_MAX__ && defined YY_STDINT_H \
	       && UINT_LEAST8_MAX <= INT_MAX)
	typedef uint_least8_t yytype_uint8;
	#elif !defined __UINT_LEAST8_MAX__ && UCHAR_MAX <= INT_MAX
	typedef unsigned char yytype_uint8;
	#else
	typedef short yytype_uint8;
	#endif

and this from gcc:

	#define __UINT_LEAST8_MAX__ 0xff
	#define __INT_MAX__ 0x7fffffff
	#define __UINT_LEAST8_TYPE__ unsigned char

It's the first part of the clause that is being selected and ending up with

	typedef unsigned char yytype_uint8;

Andy