Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-19 Thread Julien ÉLIE
Hi all, - Second is to rewrite your condition using AS_IF, which automatically "hoists" the dependency AC_PROG_CPP (and any other dependencies) outside of the if condition. I just wanted to thank you for this explanation. I was not affected by the original issue, but your answer was

Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-19 Thread Thomas Petazzoni
Hello, On Tue, 12 Apr 2016 11:05:51 -0400, Nick Bowler wrote: > There are several basic solutions: > > - First, you can just expand AC_PROG_CPP directly and unconditionally > before your if. This will ensure the macro is available in both cases. > > - Second is to rewrite your condition

Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-18 Thread Paul Eggert
On 04/12/2016 08:24 AM, Eric Blake wrote: Also, checking for is pointless these days. You can portably assume a C89 compiler (and these days, often a C99 compiler), which guarantees is present. Although it's safe to assume C89ish (or even C99ish) these days, there is the possibility that

Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-18 Thread Earnie
On 4/12/2016 11:24 AM, Eric Blake wrote: > > Also, checking for is pointless these days. You can portably > assume a C89 compiler (and these days, often a C99 compiler), which > guarantees is present. > But removing that check would thwart the purpose of autoconf being able to provide legacy

Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-12 Thread YuGiOhJCJ Mailing-List
On Tue, 12 Apr 2016 11:05:51 -0400 Nick Bowler <nbow...@draconx.ca> wrote: > Hi, > > On 2016-04-12, YuGiOhJCJ Mailing-List <yugiohjcj-mailingl...@laposte.net> > wrote: > [snip exposition] > > So, I would like to call the AC_CHECK_HEADER macro on a condition: &g

Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-12 Thread Eric Blake
On 04/12/2016 09:05 AM, Nick Bowler wrote: > > But in your second instance, the first expansion of AC_CHECK_HEADER > expands AC_PROG_CPP inside an "if". The result is that no preprocessor > is checked in the "else" case. You can see this in the configure output, > the following line is only

Re: Call the AC_CHECK_HEADER macro on a condition

2016-04-12 Thread Nick Bowler
Hi, On 2016-04-12, YuGiOhJCJ Mailing-List <yugiohjcj-mailingl...@laposte.net> wrote: [snip exposition] > So, I would like to call the AC_CHECK_HEADER macro on a condition: > AC_INIT([my-project], [20160412]) > AM_INIT_AUTOMAKE > AM_PROG_CC_C_O > if

Call the AC_CHECK_HEADER macro on a condition

2016-04-12 Thread YuGiOhJCJ Mailing-List
uld not be done. So, I would like to call the AC_CHECK_HEADER macro on a condition: AC_INIT([my-project], [20160412]) AM_INIT_AUTOMAKE AM_PROG_CC_C_O if test "x$host" == xavr; then AC_CHECK_HEADER([avr/io.h], [], [AC_MSG_ERROR([missing header: avr/io.h])]) AC_CHECK_