GPL requirements vs. "some of which are compiled with GCC" terms in special exceptions?

[Mark Millard]

While investigating powerpc64 C++ exception handling for
builds under devel/powerpc64-gcc I ran into the following
in /usr/src/contrib/gcc/unwind-dw2-fde-glibc.c :

/* As a special exception, if you link this library with other files,
   some of which are compiled with GCC, to produce an executable,
   this library does not by itself cause the resulting executable
   to be covered by the GNU General Public License.
   This exception does not however invalidate any other reasons why
   the executable file might be covered by the GNU General Public License.  */

So in contexts were clang/llvm is used to exclusion . . . are
any such files in use? (I happen to be using devel/powerpc64-gcc at
the moment.)

For me this has no real implications: I do not distribute
my experiments. But I was surprised by what I read.

Looking I find:

# grep -r "some of which are compiled with GCC" /usr/src/* | more
/usr/src/contrib/gcc/config/i386/gthr-win32.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/ia64/crtend.asm:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/ia64/fde-glibc.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/ia64/crtbegin.asm:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/ia64/lib1funcs.asm:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/ia64/crtfastmath.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/ia64/unwind-ia64.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/mips/mips16.S:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/config/vxlib.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/libgcc2.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-posix95.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-posix.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-posix.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gbl-ctors.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-gnat.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-rtems.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-vxworks.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-dce.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-nks.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-tpf.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-aix.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-lynx.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-solaris.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gcov-io.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-gnat.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-single.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/gthr-win32.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/tsystem.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/typeclass.h:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/unwind-dw2-fde-glibc.c:   some of which are compiled with GCC, to produce an executable,
/usr/src/contrib/gcc/unwind-dw2-fde-darwin.c:   some of which are compiled with GCC, to produce an executable,

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)