Hi Willy,
On 18:30 Sun 29 Sep , Willy Tarreau wrote:
> That's problematic. The issue was created by the addition of
> pcre-config
> because some people could not build on their systems in the past. The whole
> mess started with the lib64 subdir that broke basically every software
> relying on $FOO/lib. So some users had PCRE in /usr/local/{include,lib64}
> and could not specify a working PCREDIR. Thus we switched to pcre-config.
> And finally since pcre-config is still wrong on some systems (eg: when you
> want to use an alternate version such as the JIT-enabled one), we offered
> the support for separate PCRE_LIB / PCRE_INC.
Still, this approach does not properly work on most distributions
anymore. Debian and Ubuntu are shipping most of the libraries under
/usr/lib/<arch>-linux-gnu, but the libdir generated using ${prefix}/lib
is still /usr/lib. pcre-config can output the correct output path:
$ pcre-config --libs
-L/usr/lib/x86_64-linux-gnu -lpcre
but we would still end up inserting a system library path using -L.
> So maybe we should in fact stop setting PCREDIR to $(pcre-config --prefix),
> which will result in PCRE_INC/PCRE_LIB remaining silent unless PCREDIR is
> forced. I suspect the following patch should fix it :
>
> diff --git a/Makefile b/Makefile
> index 0529e89..89f9f39 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -544,7 +544,6 @@ ifneq ($(USE_PCRE)$(USE_STATIC_PCRE)$(USE_PCRE_JIT),)
> # Forcing PCREDIR to an empty string will let the compiler use the default
> # locations.
>
> -PCREDIR := $(shell pcre-config --prefix 2>/dev/null || echo
> /usr/local)
> ifneq ($(PCREDIR),)
> PCRE_INC := $(PCREDIR)/include
> PCRE_LIB := $(PCREDIR)/lib
>
Looks good to me, that's what we're essentially doing for the Debian
package right now anyway. Another approach would be to manually specify
the path to pcre-config (e.g. using a PCRE_CONFIG variable) if desired
and get `pcre-config --libs` and `pcre-config --cflags` from there if
specified. But pcre is a simple use-case, just specifying includes and
libdir should be enough.
Thanks,
Apollon
