[vsipl++] [patch] Benchmarks build issue.

[Jules Bergmann]

Don McCoy wrote:
> This patch fixes a library path issue with the benchmarks/ directory. 
> The came about due to the change in location of the FFTW library files 
> (from vendor/fftw/lib to lib/).

Don, this looks good, please check it in. thanks -- Jules

> 
> I did have one question.  In debugging, I noted that $^ contains only 
> the .o files and not the .a files from $(libs).  That is good, because 
> it would work correctly otherwise.  But why is this so?  Reading the 
> documentation didn't seem to help.

The reason this is OK is that the $(LIBS) variable (which is used in the 
rule) has the effect of including the .a files from $(libs) (which is 
used in the dependency.

For example, if you are linking against the built-in fftw3, then

    LIBS will have -lfftw3f, and
    libs will have lib/fftw3f.a

the compile command will have '-Llib -lfftw3f', causing it to use 
lib/fftw3f.a from the dependency.

I suppose we could simplify by using $(libs) in both the dependency and 
the command, but we would still have to build $(LIBS) for external use 
(it goes into the .pc) file, and $(LIBS) may have other external 
libraries, meaning we would end up using $(libs) and $(LIBS_NOT_IN_libs) :)

				-- Jules

-- 
Jules Bergmann
CodeSourcery
jules at codesourcery.com
(650) 331-3385 x705