Re: [[email protected]: [Buildroot & ArchLinux] can not build host-m4 on machine with glibc-2.28 installed]

lib/freadahead.c  Not OK:
   freadahead.c:32:26: error: '_IO_IN_BACKUP' undeclared (first use in this function)

I just fix it by my own patch.

diff -upr a/lib/freadahead.c b/lib/freadahead.c
--- a/lib/freadahead.c     2016-12-31 21:54:41.000000000 +0800
+++ b/lib/freadahead.c     2018-08-08 16:12:40.522952171 +0800
@@ -25,7 +25,13 @@
 size_t
 freadahead (FILE *fp)
 {
-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+#if defined __GNU_LIBRARY__ && __GLIBC_PREREQ(2, 28)
+   /* NOTE:                                             */
+   /*     glibc-2.28 removed /usr/include/bits/libio.h. */
+   /*     The internal symbols not avaliable            */
+   return 0;
+
+#elif defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
   if (fp->_IO_write_ptr > fp->_IO_write_base)
     return 0;
   return (fp->_IO_read_end - fp->_IO_read_ptr)

diff -upr a/lib/fseeko.c b/lib/fseeko.c
--- a/lib/fseeko.c    2016-12-31 21:54:41.000000000 +0800
+++ b/lib/fseeko.c    2018-08-08 16:13:12.399618677 +0800
@@ -47,7 +47,14 @@ fseeko (FILE *fp, off_t offset, int when
 #endif

   /* These tests are based on fpurge.c.  */
-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+#if defined __GNU_LIBRARY__ && __GLIBC_PREREQ(2, 28)
+   /* NOTE:                                             */
+   /*     glibc-2.28 removed /usr/include/bits/libio.h. */
+   /*     The internal symbols not avaliable            */
+  if (fp->_IO_read_end == fp->_IO_read_ptr
+      && fp->_IO_write_ptr == fp->_IO_write_base
+      && fp->_IO_save_base == NULL)
+#elif defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
   if (fp->_IO_read_end == fp->_IO_read_ptr
       && fp->_IO_write_ptr == fp->_IO_write_base
       && fp->_IO_save_base == NULL)

On 2018-08-08 07:33:13, Eric Blake wrote:
> Date: Wed, 8 Aug 2018 07:33:13 -0500
> From: Eric Blake <[email protected]>
> To: 郑 祎 <[email protected]>, [email protected]
> Subject: Re: [[email protected]: [Buildroot & ArchLinux] can not build
>  host-m4 on machine with glibc-2.28 installed]
> User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
>  Thunderbird/52.8.0
> 
> On 08/07/2018 10:45 PM, 郑 祎 wrote:
> > ----- Forwarded message from 郑 祎 <[email protected]> -----
> > 
> > Date: Wed, 8 Aug 2018 11:15:02 +0800
> > From: 郑 祎 <[email protected]>
> > To: Gustavo Zacarias <[email protected]>
> > Cc: Peter Korsgaard <[email protected]>, Allan McRae <[email protected]>
> > Subject: [Buildroot & ArchLinux] can not build host-m4 on machine with glibc-2.28 installed
> > User-Agent: Mutt/1.10.1 (2018-07-13)
> > 
> > Hi,
> > 
> > 	I found that failure and do some hacking.
> > 
> > 	(1) m4 source, lib/freadahead.c: It use the internal symbols to guess the C runtime lib's type.
> 
> Known issue; will be fixed by the next release of m4. In the meantime, you
> can manually apply the gnulib patch mentioned here:
> 
> https://lists.gnu.org/archive/html/bug-m4/2018-08/msg00000.html
> 
> -- 
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3266
> Virtualization:  qemu.org | libvirt.org

-- 
Brock Zheng <[email protected]>
郑 祎

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