Bug#631256: eglibc: ftbfs with binutils-gold: "These critical programs are missing or too old: ld"

[Jonathan Nieder <jrnieder@gmail.com>]

Source: eglibc
Version: 2.13-7
Tags: upstream

Hi,

I believe this is already a well known problem and don't expect
anything to happen, but am filing it for reference.  eglibc does not
build with ld.gold.  There are multiple superficial reasons for
that[*] but when it comes down to it, it is because configure.in
expects "gcc -Wl,--verbose" to write a linker script and ld.gold
neither uses linker scripts internally[**] nor knows how to fake them.

Luckily, there is a simple workaround --- ld.bfd works fine.

Regards,
Jonathan


[*] 
| $ debian/rules build
[...]
| checking version of as... 2.21.52.20110606, ok
| checking for ld... ld
| checking version of ld... v. ?.??, bad
[...]
| configure: error:
| *** These critical programs are missing or too old: ld
| *** Check the INSTALL file for required versions.
| make: *** [/home/jrn/src/glibc-work/stamp-dir/configure_libc] Error 1

Wha?  glibc only wants ld 2.17 or later.  This is just a mini-bug ---
the version check hardcodes ld.bfd-style's version string and gold
does not match.

| AC_CHECK_PROG_VER(LD, $LD, --version,
|                   [GNU ld.* \([0-9][0-9]*\.[0-9.]*\)],
|                   [2.1[7-9]*|2.1[0-9][0-9]*|2.[2-9][0-9]*|[3-9].*|[1-9][0-9]*], LD=: critic_missing="$critic_missing ld")

| $ ld --version | head -1
| GNU gold (GNU Binutils for Debian 2.21.52.20110606) 1.11

No problem --- loosen the pattern to match.  Next:

| checking for -z initfirst option... yes
| checking for -z relro option... no
| configure: error: linker with -z relro support required
| make: *** [/home/jrn/src/glibc-work/stamp-dir/configure_libc] Error 1

But... ld.gold advertises relro support.

| $ ld --help | grep relro 
|   -z relro                    Where possible mark variables read-only after relocation
|   -z norelro                  Don't mark variables read-only after relocation

Unfortunately, the configure script checks for it by reading the
linker script, and unlike ld.bfd, ld.gold does not write a linker
script when passed the --verbose option.

|   if AC_TRY_COMMAND([${CC-cc} -v --help 2>&1|grep "z relro" 1>&AS_MESSAGE_LOG_FD])
|   then
|     if AC_TRY_COMMAND([${CC-cc} -Wl,--verbose 2>&1|grep DATA_SEGMENT_RELRO_END 1>&AS_MESSAGE_LOG_FD])
|     then
|       libc_cv_z_relro=yes

| $ ld --verbose
| ld: fatal error: no input files

With that hint, it's easy to find other places that read linker
scripts for other purposes.

[**] http://www.airs.com/blog/archives/138