try flags from default compiler activation

recipes/x13as/build.sh

@@ -1,24 +1,13 @@
 #!/bin/bash
 set -ex
 
-if [[ "$target_platform" == linux-* ]]; then
-    # where libquadmath is found in our setup
-    export LDFLAGS="-L$CONDA_BUILD_SYSROOT/../lib"
-    # needs to explicitly link glibc
-    export LDFLAGS="-lc -L$CONDA_BUILD_SYSROOT/lib64"
-else
-    export LDFLAGS="-framework CoreFoundation"
-fi
-# need to link to libgfortran
-export LDFLAGS="$LDFLAGS -lgfortran"
-
 cd ascii
 # the makefiles are only makefile _templates_, but basically functional;
 # to avoid use of perl for mkmf, just execute the template and then
 # do the installation step manually
-make FC=$FC LINKER=$BUILD_PREFIX/bin/ld LDFLAGS="$LDFLAGS" install -f makefile.gf
+make FC="$FC $FFLAGS" LINKER=$BUILD_PREFIX/bin/ld LDFLAGS="$LDFLAGS" install -f makefile.gf
 cp ./x13as_ascii $PREFIX/bin
 
 cd ../html
-make FC=$FC LINKER=$BUILD_PREFIX/bin/ld LDFLAGS="$LDFLAGS" install -f makefile.gf
+make FC="$FC $FFLAGS" LINKER=$BUILD_PREFIX/bin/ld LDFLAGS="$LDFLAGS" install -f makefile.gf
 cp ./x13as_html $PREFIX/bin