Re: [Lynx-dev] Porting the configure script to C99

[Florian Weimer]

* Thomas Dickey:

>> diff --git a/configure b/configure
>> index 97f6d1d5646d05c5..6db52b514b3b9a3c 100755
>> --- a/configure
>> +++ b/configure
>> @@ -31122,6 +31122,7 @@ else
>>  #line 31122 "configure"
>>  #include "confdefs.h"
>>  
>> +#include <stdio.h>
>>  #if HAVE_TERMIO_H
>>  #include <termio.h>
>>  #endif
>> @@ -31629,6 +31630,9 @@ else
>>  #line 31629 "configure"
>>  #include "confdefs.h"
>>  /* Thanks to Mike Rendell for this test.  */
>> +#if HAVE_UNISTD_H
>> +# include <unistd.h>
>> +#endif
>
> "middle chunk" is referring to this, I suppose.
>
> AC_INCLUDES_DEFAULT includes a lot of headers, not just this one.
>
> what problem does that #include solve?

Our configure says this at the top: “Generated by Autoconf
2.52.20210509.”  I don't think it uses AC_INCLUDES_DEFAULT yet, it
seems:

| configure: failed program was:
| #line 31629 "configure"
| #include "confdefs.h"
| /* Thanks to Mike Rendell for this test.  */
| #include <sys/types.h>
| #define NGID 256
| #undef MAX
| #define MAX(x, y) ((x) > (y) ? (x) : (y))
| 
| int
| main (void)
| {
|   gid_t gidset[NGID];
|   int i, n;
|   union { gid_t gval; long lval; }  val;
| 
|   val.lval = -1;
|   for (i = 0; i < NGID; i++)
|     gidset[i] = val.gval;
|   n = getgroups (sizeof (gidset) / MAX (sizeof (int), sizeof (gid_t)) - 1,
|                  gidset);
|   /* Exit non-zero if getgroups seems to require an array of ints.  This
|      happens when gid_t is short but getgroups modifies an array of ints.  */
|   return ((n > 0 && gidset[n] != val.gval) ? 1 : 0);
| }

Full build log is here:

  
<https://gitlab.com/fweimer-rh/fedora-modernc-logs/-/blob/fbf287fbe1e977fad4ef23390174e6f6d584f5c7/logs/l/lynx.log>

>>  #include <sys/types.h>
>>  #define NGID 256
>>  #undef MAX
>> @@ -47492,6 +47496,7 @@ else
>>  #line 47492 "configure"
>>  #include "confdefs.h"
>>  
>> +#include <stdio.h>
>
> ...shouldn't be needed, since both curses.h and slang.h include stdio.h
> (LYCurses.h includes one or the other, as well as HTUtils.h)

Okay, my mistake, but the first putchar change *is* needed:

| configure: In function 'main':
| configure:31133:1: error: implicit declaration of function 'putchar'
| 31133 | {
|       | ^      
| configure:31143: $? = 1
| configure: failed program was:
| #line 31122 "configure"
| #include "confdefs.h"
| 
| #if HAVE_TERMIO_H
| #include <termio.h>
| #endif
| #if HAVE_TERMIOS_H
| #include <termios.h>
| #endif
| int
| main (void)
| {
| putchar (0x0a)
|   ;
|   return 0;
| }

Thanks,
Florian