Unnecessary now, with the other change I made at line 23. There's a Mac-specific SuiteSparse_config_Mac.mk file. I switched the formula to use that as the base SuiteSparse_config.mk file, since it was more platform appropriate, instead of munging the generic Makefile in the formula. Seems cleaner, and would be a better base for updating the formula for new versions.

The SuiteSparse_config_Mac.mk file starts out with the BLAS and LAPACK in a similar state, so the change_make_var is redundant now. It also adds '-DNTIMER' to CF, which is necessary to prevent another link error on OS X, which showed up in the Octave build once the initial -DNCAMD/Metis link error was cleared up. I think this is new as of SuiteSparse 4.x, which is why it didn't show up in earlier formulae.

Is using "-framework Accelerate" instead of "-Wl,-framework -Wl,Accelerate" going to cause compatibility issues with alternate compilers? I just realized the arguments were formed differently.

$ diff SuiteSparse_config.mk SuiteSparse_config_Mac.mk
2c2,4
< # SuiteSparse_config.mk:  common configuration file for the SuiteSparse
---
> # SuiteSparse_config_Mac.mk:  Mac configuration file for the SuiteSparse
> # To use this configuration, delete the SuiteSparse_config.mk file that
> # comes with SuiteSparse and rename this file as SuiteSparse_config.mk .
313,317c315,319
< # F77 = gfortran
< # CF = $(CFLAGS) -O3 -fno-common -fexceptions -DNTIMER
< # BLAS = -framework Accelerate
< # LAPACK = -framework Accelerate
< # LIB = -lm
---
>   F77 = gfortran
>   CF = $(CFLAGS) -O3 -fno-common -fexceptions -DNTIMER
>   BLAS = -framework Accelerate
>   LAPACK = -framework Accelerate
>   LIB = -lm

In the end, I don't think it has an immediate effect, because these Make variables only get referenced inside Demo and Tcov targets, not the lib targets.

Sorry - should have called this out in the initial commit comments, but it slipped my mind.