[macOS Binary]pyyaml installing failed on python3.7 installed by brew #522
Description
Recently homebrew has upgraded the python3 from 3.6.5 to 3.7. And when I installed the pyyaml, which is a dependency of ROS 2.0, through pip, there was an error (looks like it's incompatible with 3.7 version)
building '_yaml' extension
creating build/temp.macosx-10.12-x86_64-3.7/ext
clang -Wno-unused-result -Wsign-compare -Wunreachable-code -fno-common -dynamic -DNDEBUG -g -fwrapv -O3 -Wall -I/usr/local/include -I/usr/local/opt/openssl/include -I/usr/local/opt/sqlite/include -I/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/include/python3.7m -c ext/_yaml.c -o build/temp.macosx-10.12-x86_64-3.7/ext/_yaml.o
In file included from ext/_yaml.c:271:
ext/_yaml.h:10:9: warning: 'PyString_CheckExact' macro redefined [-Wmacro-redefined]
#define PyString_CheckExact PyBytes_CheckExact
^
ext/_yaml.c:139:11: note: previous definition is here
#define PyString_CheckExact PyUnicode_CheckExact
^
ext/_yaml.c:1410:17: warning: assigning to 'char *' from 'const char *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
__pyx_v_value = yaml_get_version_string();
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
ext/_yaml.c:2577:52: warning: incompatible pointer types passing 'int (void *, char *, size_t, size_t *)' (aka 'int (void *, char *, unsigned long, unsigned long *)') to parameter of type 'yaml_read_handler_t *' (aka 'int (*)(void *, unsigned char *, unsigned long, unsigned long *)') [-Wincompatible-pointer-types]
yaml_parser_set_input((&__pyx_v_self->parser), __pyx_f_5_yaml_input_handler, ((void *)__pyx_v_self));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/local/include/yaml.h:1368:30: note: passing argument to parameter 'handler' here
yaml_read_handler_t *handler, void *data);
^
I eliminate this error by installing the old version, which is 3.6.5
brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/f2a764ef944b1080be64bd88dca9a1d80130c558/Formula/python.rb
Is it necessary to update the WiKi for the macOS platform to point out?