MacOS keeps using Clang instead of Gfortran as compiler and seg fault when using -mcmodel=large

I'm trying to compile Tlusty and Synspec which are programs to generate model of stellar atmospheres and synthetic spectra. As in the guide that you can find here https://arxiv.org/pdf/2104.02829 I'm at the point where I have to compile Tlusty and Synspec using gfortran and I need -mcmodel=large to allocate more memory (I'm unsure whether this is the real reason but it should be something similar). If you want to check in the guide I linked above, look at section 5 (5.3 for a summary) and 6. Here I just put the output of my terminal

:~/tlusty208-package/tl208-s54/tlusty$ gfortran -fno-automatic -mcmodel=large -o tlusty.exe tlusty208.f 

tlusty208.f:13753:72:

13753 |   230    A(I,J)=SUM
      |                                                                        1
Warning: Fortran 2018 deleted feature: DO termination statement which is not END DO or CONTINUE with label 230 at (1)
tlusty208.f:33348:72:

33348 |          DO 230 J=1,NMU
      |                                                                        1
Warning: Fortran 2018 deleted feature: Shared DO termination label 230 at (1)
clang: error: unable to execute command: Segmentation fault: 11
clang: error: clang integrated assembler command failed due to signal (use -v to see invocation)
Apple clang version 17.0.0 (clang-1700.0.13.3)
Target: x86_64-apple-darwin24.4.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
clang: note: diagnostic msg: Error generating preprocessed source(s) - no preprocessable inputs.

I noticed several people have a similar problem and they say the path to gfortran should be put before the one of clang. However, this seems to be true already.

~/tlusty208-package/tl208-s54/tlusty$ which gfortran

/usr/local/bin/gfortran

~/tlusty208-package/tl208-s54/tlusty$ which clang

/usr/bin/clang

~/tlusty208-package/tl208-s54/tlusty$ gfortran --version

GNU Fortran (Homebrew GCC 14.2.0_1) 14.2.0
Copyright (C) 2024 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

~/tlusty208-package/tl208-s54/tlusty$ clang --version

Apple clang version 17.0.0 (clang-1700.0.13.3)
Target: x86_64-apple-darwin24.4.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

~/tlusty208-package/tl208-s54/tlusty$ echo $PATH

...
/usr/local/bin:
...
/usr/bin:
...

Where above I removed the other paths and substituted them with ...

If I don't use -mcmodel=large I have this problem.

~/tlusty208-package/tl208-s54/tlusty$ gfortran -fno-automatic -O3 -o tlusty.exe tlusty208.f 
tlusty208.f:13753:72:

13753 |   230    A(I,J)=SUM
      |                                                                        1
Warning: Fortran 2018 deleted feature: DO termination statement which is not END DO or CONTINUE with label 230 at (1)
tlusty208.f:33348:72:

33348 |          DO 230 J=1,NMU
      |                                                                        1
Warning: Fortran 2018 deleted feature: Shared DO termination label 230 at (1)
ld: fixup error (kind=x86_64_was_rip_got_load_elide_got) at '_divstr_.part.0'+0x8 from ccOcdtfu.o, 32-bit RIP-relative reference out of range (displacement=2279953044, max is +/-2GB), from 0x1000008C8 to 0x187E55B60 ('_straux_')
final section layout:
    __PAGEZERO           addr=0x000000000, size=0x100000000, fileOffset=0x00000000, fileSize=0x00000000
    __TEXT               addr=0x100000000, size=0x000159000, fileOffset=0x00000000, fileSize=0x00159000
        __text           addr=0x1000008c0, size=0x000115eee, fileOffset=0x000008c0
        __text_startup   addr=0x1001167b0, size=0x00000001f, fileOffset=0x001167b0
        __stubs          addr=0x1001167d0, size=0x000000108, fileOffset=0x001167d0
        __cstring        addr=0x1001168d8, size=0x00000000c, fileOffset=0x001168d8
        __const          addr=0x100116900, size=0x000036bdc, fileOffset=0x00116900
        __eh_frame       addr=0x10014d4e0, size=0x00000b798, fileOffset=0x0014d4e0
    __DATA_CONST         addr=0x100159000, size=0x000001000, fileOffset=0x00159000, fileSize=0x00001000
        __got            addr=0x100159000, size=0x0000001e8, fileOffset=0x00159000
        __const          addr=0x1001591e8, size=0x0000000d0, fileOffset=0x001591e8
    __DATA               addr=0x10015a000, size=0x0aaf05000, fileOffset=0x0015a000, fileSize=0x00017000
        __data           addr=0x10015a000, size=0x0000164a0, fileOffset=0x0015a000
        __bss            addr=0x1001704a0, size=0x01a6d19a0, fileOffset=0x00000000
        __common         addr=0x11a841e40, size=0x09081cc68, fileOffset=0x00000000
    __LINKEDIT           addr=0x1ab05f000, size=0x000021000, fileOffset=0x00171000, fileSize=0x000207d0
collect2: error: ld returned 1 exit status

Thank you!!

P.S. I add also that I checked gcc --version and it was pointing at clang, so I put these lines in my bash profile

alias gcc='/usr/local/bin/gcc-14'
alias g++='/usr/local/bin/g++-14'
alias gfortran='/usr/local/bin/gfortran-14'
export FC=/usr/local/bin/gfortran-14
export F77=/usr/local/bin/gfortran-14

but yet I get the same exact error, and clang is still being used.