On Wed, 28 Feb 2001, Adam C Powell IV wrote:
> > but it looks like what you need to do here
> > is reference another makefile variable called MPI_HOME.
> Yup.
> > The way to this is
> > with the syntax $(MPI_HOME) -- note the parens in place of braces. I
> > believe
> > ${MPI_HOME} references a non-existent /environment/ variable. (Elsewhere
> > the
> > braces may indeed be correct, since you mention the use of multiple
> > makefiles,
> > but if you need to reference a Makefile variable set in the same file, you
> > should normally use parentheses.)
> I see. So something has changed recently in unstable such that braces don't
> always work
> any more? I usually use parentheses myself, but upstream has braces all over
> the place-
> I assumed they were interchangable (okay, so I'm a "make" newbie :-).
> So why do braces work everywhere else in the makefile and all of the included
> files? Why
> do they fail in exactly the same place on every architecture? Do I need to
> do a massive
> global search and replace to switch braces to parentheses everywhere??
> I can't find anything relevant in the make info page either...
The only comment I find in the info docs is
To substitute a variable's value, write a dollar sign followed by
the name of the variable in parentheses or braces: either `$(foo)' or
`${foo}' is a valid reference to the variable `foo'.
so I may have dreamed up the distinction between the two usages. I certainly
got that impression /some/how, though...
Upon rereading your makefile snippets, I get the impression this isn't
actually the part of makefile that's being interpreted here. I see you have
defined
MPI_LIB = -L${MPI_HOME}/lib -L${MPI_HOME}/build/LINUX/ch_p4/lib -lmpich
but the output of make includes
Using libraries: -L/usr/home/hazelsct/petsc/petsc-2.0.29/lib/libO/linux_ppc
-lpetscts -lpetscsnes -lpetscsles -lpetscdm -lpetscmat -lpetscvec
-L/usr/home/hazelsct/petsc/petsc-2.0.29/lib/libO/linux_ppc -lpetsc
-L{MPI_HOME}/build/LINUX/ch_p4/lib -lmpe -lpmpich
-L/usr/X11R6/lib -lX11 -llapack -blas
-L/usr/lib/mpich/lib -L/usr/lib/mpich/build/LINUX/ch_p4/lib -lmpich -ldl -lc
-lg2c -lm
... and the correct value of MPI_LIB does appear towards the end of the
library string, well past the point where -L{MPI_HOME} shows up.
So I'm just on crack... pay no attention to anything I say. :)
Steve Langasek
postmodern programmer
