Re: bison-3.1.91 released [beta]

[Akim Demaille]

Hi Paul,

> Le 24 oct. 2018 à 00:27, Paul Eggert <address@hidden> a écrit :
> 
> On 10/23/18 8:23 AM, Akim Demaille wrote:
>> Fighting warnings is a nightmare.
>> Incredibly time consuming.
> 
> You have to pick your battles. I shut off warnings that are more trouble than 
> they're worth. This particular warning, though, is worthwhile as the program 
> can have undefined behavior.

Yes, I agree.  But ICC is incredibly picky on code generated by Flex
2.5.35.  That’s the warnings that are currently annoying me.  And ICC’s
documentation about pragma is quite unclear, so I don’t know yet what’s
the cleanest/simplest way to avoid this.

(see below too)


> examples/calc++/scanner.cc(928): error #2259: non-pointer conversion from 
> "flex_int32_t={int}" to "YY_CHAR={unsigned char}" may lose significant bits
>                       register YY_CHAR yy_c = yy_ec[YY_SC_TO_UI(*yy_cp)];
>                                               ^
> 
> examples/calc++/scanner.cc(938): error #2259: non-pointer conversion from 
> "flex_int32_t={int}" to "YY_CHAR={unsigned char}" may lose significant bits
>                                       yy_c = yy_meta[(unsigned int) yy_c];
>                                            ^
> 
> examples/calc++/scanner.cc(951): error #1682: implicit conversion of a 64-bit 
> integral type to a smaller integral type (potential portability problem)
>               YY_DO_BEFORE_ACTION;
>               ^
> 
> examples/calc++/scanner.cc(1263): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>                       YY_CURRENT_BUFFER_LVALUE->yy_buf_size - number_to_move 
> - 1;
>                       ^
> 
> examples/calc++/scanner.cc(1276): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>                               int new_size = b->yy_buf_size * 2;
>                                              ^
> 
> examples/calc++/scanner.cc(1297): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>                       num_to_read = YY_CURRENT_BUFFER_LVALUE->yy_buf_size -
>                                   ^
> 
> examples/calc++/scanner.cc(1306): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>               YY_INPUT( 
> (&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move]),
>               ^
> 
> examples/calc++/scanner.cc(1306): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>               YY_INPUT( 
> (&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move]),
>               ^
> 
> examples/calc++/scanner.cc(1367): error #2259: non-pointer conversion from 
> "flex_int32_t={int}" to "YY_CHAR={unsigned char}" may lose significant bits
>               register YY_CHAR yy_c = (*yy_cp ? yy_ec[YY_SC_TO_UI(*yy_cp)] : 
> 1);
>                                       ^
> 
> examples/calc++/scanner.cc(1377): error #2259: non-pointer conversion from 
> "flex_int32_t={int}" to "YY_CHAR={unsigned char}" may lose significant bits
>                               yy_c = yy_meta[(unsigned int) yy_c];
>                                    ^
> 
> examples/calc++/scanner.cc(1410): error #2259: non-pointer conversion from 
> "flex_int32_t={int}" to "YY_CHAR={unsigned char}" may lose significant bits
>                       yy_c = yy_meta[(unsigned int) yy_c];
>                            ^
> 
> examples/calc++/scanner.cc(1814): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>               num_to_alloc = (yy_buffer_stack_max) + grow_size;
>                            ^
> 
> examples/calc++/scanner.cc(1854): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>       b->yy_n_chars = b->yy_buf_size;
>                     ^
> 
> examples/calc++/scanner.cc(1878): error #1682: implicit conversion of a 
> 64-bit integral type to a smaller integral type (potential portability 
> problem)
>       return yy_scan_bytes(yystr,strlen(yystr) );
>                                  ^




Sometimes ICC’s warnings don’t make sense to me.  For instance:

> src/muscle-tab.c(413): warning #3179: deprecated conversion of string literal 
> to char* (should be const char*)
>     char const *fmt = !eq && value && *value ? "%%define %s %s" : "%%define 
> %s";
>                                                                 ^
> 
> src/muscle-tab.c(497): warning #188: enumerated type mixed with another type
>         muscle_percent_define_how how_old = atoi (muscle_find_const 
> (how_name));
>                                             ^
> 
> src/muscle-tab.c(529): warning #3179: deprecated conversion of string literal 
> to char* (should be const char*)
>     char const *val = value ? "" : "false";
>                                  ^
> 
> src/muscle-tab.c(707): warning #188: enumerated type mixed with another type
>                   complain_indent (&loc, complaint | no_caret | silent, &i,
>                                          ^


And

> @@.c(966): error #2259: non-pointer conversion from "int" to 
> "yybool={unsigned char}" may lose significant bits
>     return yyaction == 0;
>            ^

etc.