Build problem when copying __pycache__, Sage 8.5.beta4

[Markus Wageringel]

When I try to compile Sage 8.5.beta4 using `make distclean && make build` on OS X 10.13.6, I get an error as below. It fails at copying the directory "src/bin/__pycache__". Manually copying over the directory solves the problem, so this is probably easy to fix, but I am not sure where this `cp` command is invoked.

Markus

...
[sagelib-8.5.beta4] Discovered Python/Cython sources, time: 0.10 seconds.

[sagelib-8.5.beta4] Building interpreters for fast_callable

[sagelib-8.5.beta4] sage/rings/complex_double.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] sage/rings/complex_number.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] sage/rings/integer.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] sage/rings/complex_mpc.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] sage/rings/rational.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] sage/rings/real_double.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] sage/rings/real_mpfr.pyx: cannot find cimported module 'gmpy2'

[sagelib-8.5.beta4] warning: Replacing library search directory in linker command:

[sagelib-8.5.beta4]   "/usr/local/Cellar/openssl/1.0.2o_2/lib" -> "/Applications/SageMath/local/lib"

[sagelib-8.5.beta4] 

[sagelib-8.5.beta4] Executing 0 commands (using 1 thread)

[sagelib-8.5.beta4] Time to execute 0 commands: 0.12 seconds.

[sagelib-8.5.beta4] Total time spent compiling C/C++ extensions: 0.34 seconds.

[sagelib-8.5.beta4] if [ "$UNAME" = "CYGWIN" ]; then                         \

[sagelib-8.5.beta4]     sage-rebase.sh "$SAGE_LOCAL" 2>/dev/null;            \

[sagelib-8.5.beta4] fi

[sagelib-8.5.beta4] 

[sagelib-8.5.beta4] real 0m10.015s

[sagelib-8.5.beta4] user 0m6.071s

[sagelib-8.5.beta4] sys 0m2.857s

cp /Applications/SageMath/src/bin/__pycache__ /Applications/SageMath/local/bin/__pycache__

cp: /Applications/SageMath/src/bin/__pycache__ is a directory (not copied).

make[3]: *** [/Applications/SageMath/local/bin/__pycache__] Error 1

make[2]: *** [all-build] Error 2

real 0m10.581s

user 0m6.451s

sys 0m3.018s

***************************************************************

Error building Sage.

The following package(s) may have failed to build (not necessarily

during this run of 'make all-build'):

The build directory may contain configuration files and other potentially

helpful information. WARNING: if you now run 'make' again, the build

directory will, by default, be deleted. Set the environment variable

SAGE_KEEP_BUILT_SPKGS to 'yes' to prevent this.