* ld-elfcomm/common1b.c (dummy1): Mark the variable for GCC as USED.
* ld-shared/main.c (main): Move the P variable only to the places where
it is used.
* ld-bootstrap/bootstrap.exp: Rebuild tmpdir/ld2 with tmpdir/ld3
on Linux/mips.
* ld-elfvers/vers.exp: Also run on istarget Linux/mips.
* ld-elfvsb/elfvsb.exp: Likewise.
* ld-shared/shared.exp: Likewise.
* ld-selective/selective.exp: Mark selective2, selective3,
selective4 and selective5 xfail on Linux/mips.
* ld-shared/main.c: Skip invalid -Bsymbolic tests on Linux/mips.
* symbolic.dat: Remove invalid -Bsymbolic tests on Linux/mips.
* ld-srec/srec.exp: Add Linux/mips to xfail.
