| #! @PERL@ |
| |
| # This script handles linking the tool executables on Linux, |
| # statically and at an alternative load address. |
| # |
| # Linking statically sidesteps all sorts of complications to do with |
| # having two copies of the dynamic linker (valgrind's and the |
| # client's) coexisting in the same process. The alternative load |
| # address is needed because Valgrind itself will load the client at |
| # whatever address it specifies, which is almost invariably the |
| # default load address. Hence we can't allow Valgrind itself (viz, |
| # the tool executable) to be loaded at that address. |
| # |
| # Unfortunately there's no standard way to do 'static link at |
| # alternative address', so these link_tool_exe_*.in scripts handle |
| # the per-platform hoop-jumping. |
| # |
| # What we get passed here is: |
| # first arg |
| # the alternative load address |
| # all the rest of the args |
| # the gcc invokation to do the final link, that |
| # the build system would have done, left to itself |
| # |
| # We just let the script 'die' if something is wrong, rather than do |
| # proper error reporting. We don't expect the users to run this |
| # directly. It is only run as part of the build process, with |
| # carefully constrained inputs. |
| # |
| # Linux specific complications: |
| # |
| # - need to support both old GNU ld and gold: use -Ttext= to |
| # set the text segment address. |
| # |
| # - need to pass --build-id=none (that is, -Wl,--build-id=none to |
| # gcc) if it accepts it, to ensure the linker doesn't add a |
| # notes section which ends up at the default load address and |
| # so defeats our attempts to keep that address clear for the |
| # client. However, older linkers don't support this flag, so it |
| # is tested for by configure.in and is shipped to us as part of |
| # argv[2 ..]. |
| # |
| # |
| # So: what we actually do: |
| # |
| # pass the specified command to the linker as-is, except, add |
| # "-static" and "-Ttext=<argv[1]>" to it. |
| # |
| |
| use warnings; |
| use strict; |
| |
| # expect at least: alt-load-address gcc -o foo bar.o |
| die "Not enough arguments" |
| if (($#ARGV + 1) < 5); |
| |
| my $ala = $ARGV[0]; |
| |
| # check for plausible-ish alt load address |
| die "Bogus alt-load address" |
| if (length($ala) < 3 || index($ala, "0x") != 0); |
| |
| # The cc invokation to do the final link |
| my $cc = $ARGV[1]; |
| |
| # and the 'restargs' are argv[2 ..] |
| |
| # so, build up the complete command here: |
| # 'cc' -static -Ttext='ala' 'restargs' |
| |
| # For mips we need to use "--section-start=.reginfo=$ala" because |
| # "--section-start=.reginfo=$ala" will put all the sections to the |
| # specificed address ($ala) |
| my $x=`$cc -v 2>&1 | grep Target | sed 's/Target: //g'`; |
| my $arch=substr($x, 0, index($x, '-')); |
| my $cmd; |
| |
| if (($arch eq 'mips') || ($arch eq 'mipsel')) { |
| $cmd = "$cc -static -Wl,--section-start=.reginfo=$ala"; |
| } else { |
| $cmd = "$cc -static -Wl,-Ttext=$ala"; |
| } |
| |
| # Add the rest of the parameters |
| foreach my $n (2 .. $#ARGV) { |
| $cmd = "$cmd $ARGV[$n]"; |
| } |
| |
| #print "link_tool_exe_linux: $cmd\n"; |
| |
| |
| # Execute the command: |
| my $r = system("$cmd"); |
| |
| if ($r == 0) { |
| exit 0; |
| } else { |
| exit 1; |
| } |