[cmake] set -D__ACCELERATE on macOS if building with the Accelerate framework

[dev-zero]

is this still needed? https://developer.apple.com/documentation/accelerate/blas suggests that sdot in Accelerate returns a float, but the __ACCELERATE defs suggest a double:

#if defined (__ACCELERATE)
      REAL(KIND=real_8), EXTERNAL                        :: SCNRM2, SDOT
#else
      REAL(KIND=real_4), EXTERNAL                        :: SCNRM2, SDOT
#endif

[alazzaro]

From my test on High Sierra, it looks like that we need the __ACCELERATE macro. This is already documented in the Makefile.inc.

[dev-zero]

CMake doesn't set it (yet)

[dev-zero]

for CMake I have to figure out how to detect whether we are linking against Accelerate and enabled the flag conditionally

[dev-zero]

even with -DACCELERATE do the tests fail on tcopt1 (High Sierra) and Travis:

https://travis-ci.org/dev-zero/dbcsr/jobs/456879432

[alazzaro]

could you confirm that you are using -D__ACCELERATE?

[alazzaro]

It seems that it is still failing... Could you try to run makefile?
The only thing I do is to uncomment:

FCFLAGS += -D__NO_STATM_ACCESS -D__ACCELERATE

at the end of Makefile.inc

[dev-zero]

It's ok. Forgot that we also have to define -D__ACCELERATE directly for the tests.

[alazzaro]

OK, great, it works now, but the linking of the C++. I see that you are using

/Applications/Xcode-9.4.1.app/Contents/Developer/usr/bin/g++

which (see my previous post) point to LLVM. Brew installs g++-8. Could you check that?

[dev-zero]

since the point of CMake is to hide away this kind of complexity, I added a different solution da2a53e which solved the issue on tcopt1.

[dev-zero]

solved via #98