bug#30120: 26.0.90; Building with X toolkit without toolkit scroll bars broken on release branch and master

[Eli Zaretskii]

> Date: Mon, 15 Jan 2018 10:39:46 +0100
> From: martin rudalics <rudalics@gmx.at>
> 
> Building with an X toolkit without toolkit scroll bars currently fails
> here as
> 
> 
> CFLAGS='-O0 -g3' ../configure --with-gnutls=no --without-pop  
> --enable-gcc-warnings=warn-only --with-x-toolkit=lucid 
> --without-toolkit-scroll-bars --enable-checking=yes 
> --enable-check-lisp-object-type=yes
> make -j2 WERROR_CFLAGS=
> 
> 
> In file included from ./string.h:49:0,
>                   from ../../lib/explicit_bzero.c:28:
> ./stddef.h:93:3: error: conflicting types for ‘max_align_t’
> In file included from ./stddef.h:55:0,
>                   from ./string.h:49,
>                   from ../../lib/explicit_bzero.c:28:
> /usr/lib/gcc/x86_64-linux-gnu/4.7/include/stddef.h:426:3: note: previous 
> declaration of ‘max_align_t’ was here
> make[1]: *** [explicit_bzero.o] Fehler 1
> make[1]: *** Warte auf noch nicht beendete Prozesse...
> In file included from ./unistd.h:56:0,
>                   from ../../lib/fcntl.c:28:
> ./stddef.h:93:3: error: conflicting types for ‘max_align_t’
> In file included from ./stddef.h:55:0,
>                   from ./unistd.h:56,
>                   from ../../lib/fcntl.c:28:
> /usr/lib/gcc/x86_64-linux-gnu/4.7/include/stddef.h:426:3: note: previous 
> declaration of ‘max_align_t’ was here
> make[1]: *** [fcntl.o] Fehler 1
> make[1]: Leaving directory `/home/martin/emacs-git/release/obj-lucid-no/lib'
> make: *** [lib] Fehler 2
> 
> 
> both on the release branch and on master.  A GTK build fails
> in a similar way.

Strange.  Are you sure you don't have stale files from a previous
build?

What do you have on line 88?  It should be this:

#if ! (0 || defined _GCC_MAX_ALIGN_T)

If so, it means the configure script determined that your platform
doesn't have a definition of max_align_t, is that what you see in
config.log?  And if that's indeed so, how come the system header
stddef.h does have it?  (And why is your system stddef.h from GCC 4.7,
is that your real GCC version?)

Can you show what's around line 426 in
/usr/lib/gcc/x86_64-linux-gnu/4.7/include/stddef.h?