Something Apple did in either the latest update to Mojave or the latest Xcode breaks gfortran's (8.3.0) ability to find the system library. I updated to the latest macports recently, too. gfortran 8.3.0 that compiled code easily under previous versions of Mojave/Xcode/macports now throws an error:
M5118 error on build: ld: library not found for -lSystem collect2: error: ld returned 1 exit status make[1]: *** [../lab/map51] Error 1 make: *** [build] Error 2 with gfortran 8.3.0 Does anyone know anything about this? DN David C Nicholls, Research School of Astronomy & Astrophysics Australian National University