[petsc-dev] Problem with petsc.pc when configured with --with-single-library=0

[Barry Smith]

   I know nothing about the conventions for these files. I would say we should put them in, otherwise the file is not useful on many systems.

   Barry

> On Mar 1, 2017, at 10:22 AM, Jed Brown <jed at jedbrown.org> wrote:
> 
> Barry and Garth, should we include RPATH flags in the Libs field of
> PETSc.pc?  We normally include them in makefiles because PETSc is often
> installed to places that aren't in the search path and environment
> variables (LD_LIBRARY_PATH) are evil.
> 
> Are you aware of any conventions for handling RPATH in pkg-config?
> There is --libs-only-l, --libs-only-L, and --libs-only-other so someone
> could filter out the rpath flags by using only the first two.
> 
> I put this in a Makefile:
> 
> PETSc.pc := $(PETSC_DIR)/$(PETSC_ARCH)/lib/pkgconfig/PETSc.pc
> 
> CC := $(shell pkg-config --variable=ccompiler $(PETSc.pc))
> CPPFLAGS := $(shell pkg-config --cflags-only-I $(PETSc.pc))
> CFLAGS := $(shell pkg-config --cflags-only-other $(PETSc.pc))
> LDFLAGS := $(shell pkg-config --libs-only-L --libs-only-other $(PETSc.pc))
> LDLIBS := $(shell pkg-config --libs-only-l $(PETSc.pc)) -lm
> 
> 
> With no other targets (i.e., using only built-in rules), I can build
> examples in the current directory.  E.g.,
> 
> $ make ex5
> mpicc  -I/home/jed/petsc/include -I/home/jed/petsc/ompi-opt/include -L/home/jed/petsc/ompi-opt/lib  ex5.c  -lpetscts -lpetscsnes -lpetscksp -lpetscdm -lpetscmat -lpetscvec -lpetscsys -lm -o ex5
> 
> Should we add variables for coptflags?
> 
> I feel like we should try to make the above a recommended way to build,
> as an alternative to including the makefiles that have zillions of
> undocumented non-namespaced variables.  Note that when using PETSc
> together with other packages, the above is trivial to extend and doesn't
> risk namespace collision.
> 
> Jed Brown <jed at jedbrown.org> writes:
> 
>> Garth, I put a fix in 'next'.  Dolfin configures for me now.
>> 
>> Barry, the fact that PETSc.pc has been broken for four years is why
>> someone might use FindPETSc.cmake.  (Garth changed their CMake to use
>> pkg-config instead of the uglier logic, but then it fails with no
>> debugging output.)
>> 
>> "Garth N. Wells" <gnw20 at cam.ac.uk> writes:
>> 
>>> When configuring PETSc with "--with-single-library=0", my installed 
>>> petsc.pc file looks like:
>>> 
>>> prefix=/home/garth/local/packages/petsc-test
>>> exec_prefix=${prefix}
>>> includedir=${prefix}/include
>>> libdir=/home/garth/local/packages/petsc-test/lib
>>> ccompiler=mpicc
>>> fcompiler=mpif90
>>> blaslapacklibs=-llapack -lblas
>>> 
>>> Name: PETSc
>>> Description: Library to solve ODEs and algebraic equations
>>> Version: 3.7.5
>>> Cflags: -I/home/garth/local/packages/petsc-test/include 
>>> -I/home/garth/local/packages/petsc-test/include
>>> Libs: -L/home/garth/local/packages/petsc-test/lib  -lpetsc
>>> Libs.private: -llapack -lblas -lX11 -lpthread -lm 
>>> -Wl,-rpath,/usr/lib/x86_64-linux-gnu -L/usr/lib/x86_64-linux-gnu 
>>> -Wl,-rpath,/usr/lib/gcc/x86_64-linux-gnu/6 
>>> -L/usr/lib/gcc/x86_64-linux-gnu/6 -Wl,-rpath,/lib/x86_64-linux-gnu 
>>> -L/lib/x86_64-linux-gnu -lmpichfort -lgfortran -lm -lgfortran -lm 
>>> -lquadmath -lm -lmpichcxx -lstdc++ -Wl,-rpath,/usr/lib/x86_64-linux-gnu 
>>> -L/usr/lib/x86_64-linux-gnu -Wl,-rpath,/usr/lib/gcc/x86_64-linux-gnu/6 
>>> -L/usr/lib/gcc/x86_64-linux-gnu/6 -Wl,-rpath,/usr/lib/x86_64-linux-gnu 
>>> -L/usr/lib/x86_64-linux-gnu -Wl,-rpath,/lib/x86_64-linux-gnu 
>>> -L/lib/x86_64-linux-gnu -Wl,-rpath,/usr/lib/x86_64-linux-gnu 
>>> -L/usr/lib/x86_64-linux-gnu -ldl -lmpich -lgcc_s -ldl
>>> 
>>> 
>>> Note the "Libs:". It points only to petsc (which doesn't exist), 
>>> whereas I would expect it to list each PETSc lib, i.e., petscdm, 
>>> petscksp, etc, or provide a pkg-config file for each PETSc lib.
>>> 
>>> Garth