Created attachment 275199 [details] trivial patch app-text/dvipng-1.14 fails to emerge due to invalid include of <wait.h> in special.c on OSX. It uses waitpid, and man tells the correct header for the function is <sys/wait.h>. Perhaps, the standard header for waitpid is <sys/wait.h> even on Linux.
yup it even is on Solaris, so I added your patch, thanks!