Arch Linux

Gold is a new linker, written as a drop-in replacement for gnu ld, by Google.
It can be built by passing --enable-gold to the binutils configuration script. It should have no adverse effects, but should make the new gold linker be built. Which is awesome and fast.

Then you can replace your /bin/ld with this tiny c-program, and make the proper arrengements, and voila, easy to switch between gold and plain gnu ld:
#include <stdlib.h>
#include <stdio.h>

int main(int argc, char *argv[])
{
// C at what it does best :)

const char *ld_env_var = getenv("USE_GOLD_LINKER"); // "USE_GOLD_LINKER" kids, mmmkay?
const char *linker_name = 0;
if (ld_env_var && ld_env_var[0] != '\0' ) {
// OK, the environment variable exists and it has nonzero length...
argv[0] = "/usr/bin/ld-new";
linker_name = "gold";
} else {
argv[0] = "/usr/bin/ld-old";
linker_name = "GNU ld";
}

if (execvp(*argv, argv) < 0) {
fprintf(stderr, "** exec failed. Probably the %s executable %s was not found.\n", linker_name, argv[0]);
return -1;
}

//unreachable
fprintf(stderr, "Gamma ray burst registered.\n");
return -1;
}