insufficient descriptor for gfortran

[robertladwig]

gcc 4.2.1 under macOS Big Sur 11.4

When compiling GLM v3.2.0a6 with libaed-water using gfortran, I get the error that for line 113 in src/aed_util.F90
Error: Period required in format specifier D at (1)

Changing this line to
WRITE(str, "(d12.4)") num

helps in completing the compilation though. But please note that I don't know which length the final string representing the real value should have.