New failures with autoconf master

[Ross Burton]

Hi,

So I kicked off a world build in OpenEmbedded with autoconf master as of 
this morning. Of note is that Flex and Nasm are both failing in similar 
ways with autoconf post-2.69:

nasm:
checking for uintptr_t... yes
./configure: line 6400: syntax error near unexpected token `do'
./configure: line 6400: `do :'

The code around here is:

   6393 printf "%s\n" "#define uintptr_t $ac_type" >>confdefs.h
   6394
   6395           ac_type=
   6396 fi
   6397 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
   6398        test -z "$ac_type" && break
   6399      done
   6400 fi
   6401
   6402
   6403
   6404 # Check whether --enable-pdf-compression was given.
   6405 if test ${enable_pdf_compression+y}
   6406 then :
   6407   enableval=$enable_pdf_compression;
   6408 else
   6409   enableval=yes
   6410 fi


flex:
checking for strtol... yes
./configure: command substitution: line 16785: syntax error near 
unexpected token `then'
./configure: command substitution: line 16785: `then :'
./configure: line 16777:  = xyes
then :
  cat >>confdefs.h <<_ACEOF
[pages of configure script]

The flex issue is worked around by picking this commit from flex git:

https://github.com/westes/flex/commit/c42de062bbdc7c31d7181c10a74202d493280ada

That refers to a mail sent to bug-autoconf in February 2018, with no reply:

https://lists.gnu.org/archive/html/bug-autoconf/2018-02/msg00005.html

Any thoughts?

Ross