Re: The right way to use standard variable in configure.ac

[Diego Elio Pettenò]

As John said you should use

CPPFLAGS="${CPPFLAGS} -DMACRO1 -DMACRO2"

But most likely you want to set this in DEFINES rather than CPPFLAGS,
or use AC_DEFINE directly…
Diego Elio Pettenò — Flameeyes
https://blog.flameeyes.eu/


On 3 April 2015 at 00:04, Andy Falanga (afalanga) <address@hidden> wrote:
> Hi,
>
> I placed the following in my configure.ac file:
>
> CPPFLAGS="-DMACRO1 -DMACRO2"
>
> because I found that as an example on a webpage someplace.  I reviewed so 
> many learning about the autotools that I don't recall which one now.  I did 
> this because there were some preprocessor flags that I wanted to have common 
> to all sub-makefiles.
>
> I ran into a problem today, however, where I needed to add a -I directive to 
> my CPPFLAGS in order to find the necessary headers.  Then, the problem 
> stepped in.  Because I placed this line in configure.ac, it was transcribed, 
> verbatim (as it should), into configure.  The net result: not matter what I 
> placed on the command line was ignored.  For example, the following:
>
> CPPFLAGS=-I/path/to/the/alternate/location ./configure --build=x86_64-linux 
> --host=arm-poky-linux-gnueabi
>
> The additional path wasn't being appended, it was being stomped.  Did I miss 
> a macro?  How should this be done because, obviously, I've gotten it 
> incorrect.
>
> Thanks,
> Andy