Coarrays: undefined reference to for_rtl_ICAF_LAUNCH

Hello,

I am trying to port a coarray fortran application from Windows to Linux (Ubuntu 16.04). This application compiles and works fine under Windows. I am using the Intel Fortran 19 Update 4. I applied all the compiler flags that were set on the Windows version including -coarray and -corray-num-images=10. Under Linux, when I try to compile, I get the following error:

Iwfm_f2.f90:(.text+0x76eb): undefined reference to `for_rtl_ICAF_LAUNCH'

An internet search turned nothing on this error. Can somebody let me know what I might be doing wrong?

Thanks,

Jon