message: In defaults.cmake, fix the type of PETSC_ARCH: PATH -> STRING.
diff: @@ -130,7 +130,7 @@ set(NetCDF_REQUIRED_PACKAGES "" CACHE STRING
  set(PETSC_DIR "${MFEM_DIR}/../petsc" CACHE PATH
  "Path to the PETSc main directory.")
  -set(PETSC_ARCH "arch-linux2-c-debug" CACHE PATH "PETSc build architecture.")
  +set(PETSC_ARCH "arch-linux2-c-debug" CACHE STRING "PETSc build architecture.")
  set(MPFR_DIR "" CACHE PATH "Path to the MPFR library.")
  