Re: [GM-help] Weird configure quirk on FreeBSD

[Bob F. <bfr...@si...>]

On Mon, 23 May 2005 no...@no... wrote:

>
> Can anyone explain this? It took me forever to figure out that
> to successfully configure GraphicsMagick on FreeBSD 5.3 I need
> the following configure command:
>    ./configure --with-x=no CPPFLAGS=-I/usr/local/include
> LDFLAGS='-L/usr/local/lib'
> The reason this took me so long to figure out is that the configure
> output reports that it appends "-L/usr/local/lib" to LDFLAG by default.

How odd ... but there is an explanation.

GraphicsMagick's configure script does not intentionally automatically 
add the install directory to the lib and include search paths even 
though the intial thought is that this is an obvious thing to do.

While the configure script runs, configure executes FreeType's 
freetype-config script which produces output like:

% freetype-config --libs
-L/usr/local/lib -lfreetype -lz

so GraphicsMagick adds the -L/usr/local/lib option to LDFLAGS. 
However, by the time it does this, several other libraries (e.g. 
libjpeg) have already been tested for.

So the end result is that FreeType is found, -L/usr/local/lib is used 
in the final build options, but earlier tests which needed the option 
fail.

The cure for this may be to break up the configure into one part which 
builds up the LDFLAGS/CPPFLAGS, and a second part which actually does 
the test.  The drawback to this is if the test fails, then 
LDFLAGS/CPPFLAGS will still refer to the directory which failed.

The reason why GraphicsMagick's configure script does not 
automatically add the install directory to the lib and include search 
paths is because this does not always work right.  Sometimes the user 
needs a different search path in order for things to work right.  The 
reason is that there may be two similar libraries, one of which is 
already installed in the prefix directory, but the user wants to use a 
different one in the build.  So GraphicsMagick's configure script 
leaves it up to the user.

Bob
======================================
Bob Friesenhahn
bfr...@si..., http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/