Associate statements cause 'forrtl: severe (174): SIGSEGV, segmentation fault occurred' error on ifx

[Dominick99]

The following associate statements appear to cause an error:

do_concurrent_s.f90: Line 14
do_concurrent_s.f90: Line 84
distribution_s.F90: Line 58
matcha_s.F90: Line 46
matcha_s.F90: Line 50

After replacing them, matcha can be run on the ifx compiler using:
fpm run --compiler ifx --flag "-g -O0 -traceback -coarray"

However, using:
fpm test --compiler ifx --flag "-g -O0 -traceback -coarray"

results in the following error:

build/dependencies/iso_varying_string/src/iso_varying_string.f90(1316): error #5623: **Internal compiler error: internal abort** Please report this error along with the circumstances in which it occurred in a Software Problem Report.  Note: File and line given may not be explicit cause of this error.

        string_iachar = iachar(char(c))

------------------------^

compilation aborted for build/dependencies/iso_varying_string/src/iso_varying_string.f90 (code 3)

<ERROR> Compilation failed for object " build_dependencies_iso_varying_string_src_iso_varying_string.f90.o "

<ERROR>stopping due to failed compilation

STOP 1