flags.Parse()

	architecture := arch.Set(GOARCH, *flags.Shared || *flags.Dynlink)
	if architecture == nil {
		log.Fatalf("unrecognized architecture %s", GOARCH)
	}
	ctxt := obj.Linknew(architecture.LinkArch)
	ctxt.Debugasm = flags.PrintOut
	ctxt.Debugvlog = flags.DebugV
	ctxt.Flag_dynlink = *flags.Dynlink
	ctxt.Flag_linkshared = *flags.Linkshared
	ctxt.Flag_shared = *flags.Shared || *flags.Dynlink

	}
}

func archRISCV64(shared bool) *Arch {
	register := make(map[string]int16)

	// Standard register names.
	for i := riscv.REG_X0; i <= riscv.REG_X31; i++ {
		// Disallow X3 in shared mode, as this will likely be used as the
		// GP register, which could result in problems in non-Go code,
		// including signal handlers.
		if shared && i == riscv.REG_GP {
			continue
		}

	Shared     = flag.Bool("shared", false, "generate code that can be linked into a shared library")
	Dynlink    = flag.Bool("dynlink", false, "support references to Go symbols defined in other shared libraries")
	Linkshared = flag.Bool("linkshared", false, "generate code that will be linked against Go shared libraries")

	numberFormatter func([]byte, int64)
)

// templateV7Plus fills out the V7 fields of a block using values from hdr.
// It also fills out fields (uname, gname, devmajor, devminor) that are
// shared in the USTAR, PAX, and GNU formats using the provided formatters.
//
// The block returned is only valid until the next call to
// templateV7Plus or writeRawFile.

code generated for gcc. The build process links this stub, along with
_cgo_export.c and *.cgo2.c, into a dynamic executable and then lets
cgo examine the executable. Cgo records the list of shared library
references and resolved names and writes them into a new file
_cgo_import.go, which looks like:

	//go:cgo_dynamic_linker "/lib64/ld-linux-x86-64.so.2"
	//go:cgo_import_dynamic puts puts#GLIBC_2.2.5 "libc.so.6"

	//
	// by the DECLARE_HANDLE macro in STRICT mode. The macro is declared in
	// the Windows ntdef.h header,
	//
	// https://github.com/tpn/winsdk-10/blob/master/Include/10.0.16299.0/shared/ntdef.h#L779
	if goos != "windows" {
		return false
	}
	if len(dt.Field) != 1 {
		return false
	}
	if dt.StructName != name+"__" {
		return false
	}

	-dynlink
		Support references to Go symbols defined in other shared libraries.
	-e
		No limit on number of errors reported.
	-gensymabis
		Write symbol ABI information to output file. Don't assemble.
	-o file
		Write output to file. The default is foo.o for /a/b/c/foo.s.
	-p pkgpath
		Set expected package import to pkgpath.
	-shared
		Generate code that can be linked into a shared library.
	-spectre list

files.  The first two, 6g.go and 6c.c, are a Go source file for 6g and
a C source file for 6c; both compile as part of the named package
(gmp, in this example).  The third, gcc.c, is a C source file for gcc;
it compiles into a shared object (.so) that is dynamically linked into
any 6.out that imports the first two files.

The stanza

	// #include <gmp.h>
	import "C"

is a signal to cgo.  The doc comment on the import of "C" provides