failure to do so was causing crashes on x86_64 when ctors used SSE,
which was first observed when ctors called variadic functions due to
the SSE prologue code inserted into every variadic function.
it does not work; after further consideration, a separate Scrt1.s for
pie really is essential. it would be nice if the unified approach
worked, but the linker fails to generate the correct PLT entries and
instead puts textrels in the main program, which don't work because
the kernel maps the text read-only.
new Scrt1.s will be committed soon in place of this.
this is mainly in hopes of supporting c++ (not yet possible for other
reasons) but will also help applications/libraries which use (and more
often, abuse) the gcc __attribute__((__constructor__)) feature in "C"
code.
x86_64 and arm versions of the new startup asm are untested and may
have minor problems.