Build issue between GCC 13.3 and yafyaml 1.3.0

[mathomp4]

In trying to build Baselibs today on my Mac, yaFyaml did not build successfully:

[ 94%] Built target yafyaml
[ 95%] Linking Fortran executable to_json.x
Undefined symbols for architecture arm64:
  "_is_recursive.18.6", referenced from:
      ___fy_string_MOD_copyfromstring in libyafyaml.a[6](String.F90.o)
      ___fy_string_MOD_copyfromstring in libyafyaml.a[6](String.F90.o)
      ___fy_string_MOD_copyfromstring in libyafyaml.a[6](String.F90.o)
  "_is_recursive.22.5", referenced from:
      ___fy_string_MOD_copyself in libyafyaml.a[6](String.F90.o)
      ___fy_string_MOD_copyself in libyafyaml.a[6](String.F90.o)
      ___fy_string_MOD_copyself in libyafyaml.a[6](String.F90.o)
  "_is_recursive.9.12", referenced from:
      ___fy_stringnode_MOD_clone in libyafyaml.a[38](StringNode.F90.o)
      ___fy_stringnode_MOD_clone in libyafyaml.a[38](StringNode.F90.o)
      ___fy_stringnode_MOD_clone in libyafyaml.a[38](StringNode.F90.o)
ld: symbol(s) not found for architecture arm64
collect2: error: ld returned 1 exit status
make[2]: *** [yaFyaml/src/to_json.x] Error 1
make[1]: *** [yaFyaml/src/CMakeFiles/to_json.x.dir/all] Error 2
make: *** [all] Error 2

The odd thing is, yaFyaml had been building just fine with gfortran-13. But, recently, Homebrew (where I get gfortran-13) has updated to gfortran 13.3 and I'm guessing a brew upgrade pulled that down.

Further tests show that gfortran 12.3 and NAG Fortran 7.2 are fine still.

I'm trying to build on a Linux box gfortran 13.3 there and see if this is a macOS only issue or compiler issue. I'm leaning toward the latter only because the usual "Things are broken on macOS" fix of LDFLAGS=-Wl,-ld_classic didn't help here.

[mathomp4]

I have confirmed this on Linux with spack and gcc 13.3:

     212    /usr/bin/ld: libyafyaml.a(StringNode.F90.o): in function `__fy_stringnode_MOD_clone':
  >> 213    /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/Nodes/StringNode.F90:134:(.text+0x44e): undefined r
            eference to `is_recursive.9.12'
  >> 214    /usr/bin/ld: /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/Nodes/StringNode.F90:151:(.text+0x463)
            : undefined reference to `is_recursive.9.12'
  >> 215    /usr/bin/ld: /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/Nodes/StringNode.F90:149:(.text+0x544)
            : undefined reference to `is_recursive.9.12'
     216    /usr/bin/ld: libyafyaml.a(String.F90.o): in function `__fy_string_MOD_copyself':
  >> 217    /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/String.F90:84:(.text+0x44a): undefined reference to
             `is_recursive.20.5'
  >> 218    /usr/bin/ld: /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/String.F90:99:(.text+0x45c): undefined
             reference to `is_recursive.20.5'
  >> 219    /usr/bin/ld: /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/String.F90:90:(.text+0x4f9): undefined
             reference to `is_recursive.20.5'
     220    /usr/bin/ld: libyafyaml.a(String.F90.o): in function `__fy_string_MOD_copyfromstring':
  >> 221    /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/String.F90:93:(.text+0x54e): undefined reference to
             `is_recursive.18.6'
  >> 222    /usr/bin/ld: /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/String.F90:108:(.text+0x560): undefine
            d reference to `is_recursive.18.6'
  >> 223    /usr/bin/ld: /home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-src/src/String.F90:99:(.text+0x5ee): undefined
             reference to `is_recursive.18.6'
  >> 224    collect2: error: ld returned 1 exit status
  >> 225    make[2]: *** [src/CMakeFiles/to_json.x.dir/build.make:102: src/to_json.x] Error 1
     226    make[2]: Leaving directory '/home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-build-liavynz'
  >> 227    make[1]: *** [CMakeFiles/Makefile2:353: src/CMakeFiles/to_json.x.dir/all] Error 2
     228    make[1]: Leaving directory '/home/ubuntu/tmpdir/spack-stage/spack-stage-yafyaml-1.3.0-liavynzepcx6bhtpp5eiyh34r5bcm7cb/spack-build-liavynz'
  >> 229    make: *** [Makefile:149: all] Error 2

So it's a compiler issue.