On 09/25/2011 09:14 AM, Gary V. Vaughan wrote: > Hi Paul, > > On 25 Sep 2011, at 13:09, Paul Eggert wrote: > >> On 09/24/11 22:31, Gary V. Vaughan wrote: >>> $ cc -o hello hello.c >>> cc-1241 cc: ERROR File = hello.c, Line = 7 >>> A declaration cannot appear after an executable statement in a block. >> >> You're supposed to use cc's -c99 flag, no? >> Or compile with c99? Then declarations after statements >> should work; see, for example >> <http://lists.gnu.org/archive/html/bug-gnulib/2009-02/msg00241.html>. > > D'oh! Quite right. > > There must be some side effect that -c99 has which prevents me from just > turning it on indiscriminately... Unfortunately I don't remember what, only > that I've had to go through adding braces to make extra scopes around out > of order declarations. > > I'll keep an eye out for an example and post it here when I find it. > >> Is 'configure' not doing this for you automatically? >> If so, then let's fix that. > > How will configure know whether it needs to use -c99 mode or not? I tend > to set CC and CFLAGS per host/compiler pair anyway, so I wouldn't notice > if configure is trying to pick the flags for me. > > Cheers,
AC_PROG_CC_STDC should try to enable C99 first and then C89 There is also AC_PROG_CC_C99, since autoconf 2.59c (Apr 2006). If doing this in gnulib we should also remove the -Wdeclaration-after-statement from m4/manywarnings.m4 cheers, Pádraig.
