Building pgpme-1.14.0 on OS X 10.11. From MacPorts Issue 60930 (https://trac.macports.org/ticket/60930):
```
998 :info:build warning: unknown warning option '-Wsuggest-override'; did you mean '-Wshift-overflow'? [-Wunknown-warning-option]
999 :info:build warning: unknown warning option '-Wzero-as-null-pointer-constant'; did you mean '-Wint-to-void-pointer-cast'? [-Wunknown-warning-option]
1000 :info:build editinteractor.cpp:181:29: error: use of undeclared identifier 'getenv'
1001 :info:build const char *debug_env = getenv("GPGMEPP_INTERACTOR_DEBUG");
1002 :info:build ^
1003 :info:build 2 warnings and 1 error generated.
1004 :info:build make[3]: *** [editinteractor.lo] Error 1
1005 :info:build make[3]: *** Waiting for unfinished jobs....
1006 :info:build 2 warnings generated.
```