ExternalLibraries/MPI’s detect.pl script creates entries in make.MPI.defn like this (on stampede3):

MPI_DIR      = /opt/intel/oneapi/mpi/2021.11
MPI_INC_DIRS = "/opt/intel/oneapi/mpi/2021.11/include"
MPI_LIB_DIRS = "/opt/intel/oneapi/mpi/2021.11/lib"
MPI_LIBS     = mpicxx mpifort mpi rt pthread dl

which is incorrect since make makes the double quotes part of the variables value. This is usually safe when used in the shell since -L"Foo" is the same as -LFoo but fails with Silo which stores the options in a string (and does not escape embedded quotes).

Since make does not handle spaces well anyway detect.pl should not output any quotes since the paths will never contain one.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2831/externallibraries-mpi-creates-mpi_inc_dirs