[Spice-devel] [PATCH spice-common] spice-deps: Make LZ4 check depending on function

[Pavel Grunt]

On Thu, 2016-11-24 at 05:18 -0500, Frediano Ziglio wrote:
> > LZ4 changed versioning scheme from r131 to v1.7.3 making our
> > configure
> > fail with (1.7.3 < 129).
> > 
> > Switch from version checking to checking that the necessary
> > function
> > is available.
> > ---
> >  m4/spice-deps.m4 | 6 ++++--
> >  1 file changed, 4 insertions(+), 2 deletions(-)
> > 
> > diff --git a/m4/spice-deps.m4 b/m4/spice-deps.m4
> > index adedec4..43a7d4a 100644
> > --- a/m4/spice-deps.m4
> > +++ b/m4/spice-deps.m4
> > @@ -185,12 +185,14 @@ AC_DEFUN([SPICE_CHECK_LZ4], [
> >  
> >      have_lz4="no"
> >      if test "x$enable_lz4" != "xno"; then
> > -      PKG_CHECK_MODULES([LZ4], [liblz4 >= 129], [have_lz4="yes"],
> > [have_lz4="no"])
> > +      PKG_CHECK_MODULES([LZ4], [liblz4], [
> > +          AC_SEARCH_LIBS([LZ4_compress_default], [lz4],
> > [have_lz4="yes"],
> > [have_lz4="no"])],
> > +          [have_lz4="no"])
> >  
> 
> have_lz4 by default is defined no so you could remove the assignment
> to "no", but that's not a problem.

ok

> 
> Using AC_SEARCH_LIBS and [lz4] as library you are assuming you can
> link lz4 library with -llz4 (more or less) but this can be a problem
> if you are using MingW or another cross compiler that needs other
> options. Maybe this is hidden by the fact that we just require a
> library path and is already included by another library.
> Did you try to cross compile the client for Windows?

lz4 is not available for mingw so I haven't tried it

> 
> >        if test "x$have_lz4" = "xyes"; then
> >          AC_DEFINE(USE_LZ4, [1], [Define to build with lz4
> > support])
> >        elif test "x$enable_lz4" = "xyes"; then
> > -        AC_MSG_ERROR([lz4 support requested but liblz4 could not
> > be found])
> > +        AC_MSG_ERROR([lz4 support requested but liblz4 >= 129
> > could not be
> > found])
> >        fi
> >      fi
> >      AM_CONDITIONAL(HAVE_LZ4, test "x$have_lz4" = "xyes")
> 
> Beside the cross compilation issue patch works for me.
> 
> Frediano