[petsc-users] Compile and link correctly using conf/petscvariables and conf/variables

[Satish Balay]

The idea here is - you would:

include "conf/variables" in your makefile and use PETSC_LIB in the
target - so everything works correctly.

The complexity you mention is to manage --with-single-lib=0/1. So
Instead of trying to list libraries directly in your makefile [which
becomes unportable] - I suggest you use the recommended procedure
above. PETSC_LIB will pick up all exteranlpackages currently installed
with PETSc [so even this part of the makefile will become portable]

The best thing would be to also use "conf/rules" as well in your
makefile and use PETSc compile targets for both petsc & non-petsc
sources that go into your application.

Satish

On Thu, 5 Aug 2010, Filippo Spiga wrote:

>  Dear users,
>     I look at different examples but I'm not sure to have well understood how
> to compile and link correctly using the contents of "conf/petscvariables" and
> "conf/variables". My program uses both linear and non linear solvers and
> different external packages such as superlu_dist, hypre and umfpack. I looked
> at "${PETSC_ROOT}/${PETSC_ARCH}/conf/petscvariables" to extract the right path
> to compile and link my code. Inside this file there are all these lines:
> 
> PETSC_CONTRIB_BASIC = -lpetsc
> PETSC_SNES_LIB_BASIC = -lpetsc
> PETSC_KSP_LIB_BASIC = -lpetsc
> PETSC_MAT_LIB_BASIC = -lpetsc
> PETSC_LIB_BASIC = -lpetsc
> PETSC_VEC_LIB_BASIC = -lpetsc
> PETSC_DM_LIB_BASIC = -lpetsc
> PETSC_TS_LIB_BASIC = -lpetsc
> PETSC_SYS_LIB_BASIC = -lpetsc
> PACKAGES_LIBS = ...
> 
> but there isn't a single entry that collect in the right order all of them.
> Then if I look at "${PETSC_ROOT}/${PETSC_ARCH}/conf/variables" I can find
> these lines:
> 
> PETSC_EXTERNAL_LIB_BASIC = ${EXTERNAL_LIB} ${PACKAGES_LIBS} ${PCC_LINKER_LIBS}
> PETSC_SYS_LIB_BASIC      = -lpetscsys
> PETSC_VEC_LIB_BASIC      = -lpetscvec ${PETSC_SYS_LIB_BASIC}
> PETSC_MAT_LIB_BASIC      = -lpetscmat ${PETSC_VEC_LIB_BASIC}
> PETSC_DM_LIB_BASIC       = -lpetscdm ${PETSC_MAT_LIB_BASIC}
> PETSC_KSP_LIB_BASIC     = -lpetscksp ${PETSC_DM_LIB_BASIC}
> PETSC_SNES_LIB_BASIC     = -lpetscsnes ${PETSC_KSP_LIB_BASIC}
> PETSC_TS_LIB_BASIC       = -lpetscts ${PETSC_SNES_LIB_BASIC}
> PETSC_LIB_BASIC          = ${PETSC_TS_LIB_BASIC}
> PETSC_CONTRIB_BASIC      = -lpetsccontrib
> 
> PETSC_SYS_LIB     = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_SYS_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_VEC_LIB     = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_VEC_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_MAT_LIB     = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_MAT_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_DM_LIB      = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_DM_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_KSP_LIB     = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_KSP_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_SNES_LIB    = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR}
> ${PETSC_SNES_LIB_BASIC} ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_TS_LIB      = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_TS_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_LIB         = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_LIB_BASIC}
> ${PETSC_EXTERNAL_LIB_BASIC}
> PETSC_CONTRIB     = ${C_SH_LIB_PATH} -L${PETSC_LIB_DIR} ${PETSC_CONTRIB_BASIC}
> 
> that are pretty clear. However if I look inside
> "${PETSC_ROOT}/${PETSC_ARCH}/lib" I don't  see all the -lpetsc* libraries
> mentioned above" I only have one single "libpetsc.a"
> 
> So, what's the right env variable to use? what is the right order of -lpetsc*
> statements? Can I only link "libpetsc.a"? In this last case, is my Makefile
> fully compatible and maintenable with all the future version of PETSc?
> 
> Thank you very much in advance,
> Regards
> 
>