[ long winding and weaving reply ahead .. sorry ]
> >> It looks like I did not have that set. I did have :
> >>
> >> LD=/usr/local/bin/gld
> >> LDFLAGS=-L/usr/local/lib
> >> LD_OPTIONS=-R/usr/local/lib:/usr/local/gcc4/lib -L/usr/local/lib:/usr/local/gcc4/lib
> >> LD_RUN_PATH=/usr/local/lib:/usr/local/gcc4/lib
> >> LIBTOOL=/usr/local/bin/libtool
> >>
> >> Those may be the source of my concern as LD_OPTIONS could be trouble.
> >
> > I don't think the GNU linker uses LD_OPTIONS, isn't that a Solaris ld
> > environment variable?
yep. clearly something I dragged over from one of my Solaris build servers.
Should be harmless, but useless also.
> > LD_RUN_PATH would cause your issue though. Don't do that.
I was wondering if the libs in /usr/local/gcc4/lib are being found and they
belong to GCC 4.7.3 as opposed to 4.8.0 and .. I see yes, you have mentioned
that below.
> Or if you do, don't have the older GCC libs in those paths, as they
> are being found and that's what causes the test failures. Once you've
> installed the newer GCC you might find the tests results are better,
> because the older libs don't get found.
Generally I tend to stick with a procedure of "test first" then if that looks okay,
I install. This is a chicken and egg case where I need to install first and then
run tests. Seems reasonable given that changes that have happened in the
GCC 4.8.x world.
> Is there a reason you're putting /usr/local/lib in the RPATH? Isn't it
> in the default paths searched by ldconfig anyway?
That would be part of my Solaris history showing again. I have this old UNIX
belief that anything in /usr/lib is definately considered part of the vendor OS
and will always be used by the runtime linker and/or compiler and linker with
no need for me to specify anything. Anything else, however, even things like
software pieces in /usr/lib/vmware/lib or /usr/lib/ure/lib there is no promise.
I have a philosophy, which may be wrong, that messing with crle or making
a modification to the vendor provided default link searchpath should be a
strict no no. If I were to tweak the system to search /usr/local/lib first, such
that my new libiconv and GNU gettext bits are found first then I could just
as easily place a tweaked libc in there. Perhaps I could hack in a modified
routine to extract users environment variables and session data and write
that info silently to a file somewhere. I generally think, perhaps wrongly,
that the stuff in /usr/local/lib should not be searched by default. That the
purpose of RPATH and RUNPATH inside the elf headers exist to ensure that
a given executable uses the libs I want. This allows me to build a binary
and drop it into someplace like /opt/vendorname/bin with libs inside a path
such as /opt/vendorname/lib with confidence.
An example would be my binary for gawk :
dclarke@titan $ elfdump -devl /usr/local/bin/gawk
ELF Header
ei_magic: { 0x7f, E, L, F }
ei_class: ELFCLASS32 ei_data: ELFDATA2LSB
e_machine: EM_386 e_version: EV_CURRENT
e_type: ET_EXEC
e_flags: 0
e_entry: 0x8055b60 e_ehsize: 52 e_shstrndx: 37
e_shoff: 0xe5724 e_shentsize: 40 e_shnum: 39
e_phoff: 0x34 e_phentsize: 32 e_phnum: 5
Version Needed Section: .SUNW_version
file version
libc.so.1 SUNW_1.18
SUNWprivate_1.1
libsocket.so.1 SUNW_1.4
libdl.so.1 SUNW_0.7
libm.so.1 SUNW_1.1
Dynamic Section: .dynamic
index tag value
[0] NEEDED 0x1535 libsigsegv.so.2
[1] NEEDED 0x14d2 libc.so.1
[2] NEEDED 0x1545 libintl.so.8
[3] NEEDED 0x1552 libiconv.so.2
[4] NEEDED 0x14f6 libsocket.so.1
[5] NEEDED 0x1560 libnsl.so.1
[6] NEEDED 0x150e libdl.so.1
[7] NEEDED 0x1522 libm.so.1
[8] INIT 0x80a9598
[9] FINI 0x80a95a5
[10] RUNPATH 0x156c /usr/local/lib:/usr/local/gcc4/lib
[11] RPATH 0x156c /usr/local/lib:/usr/local/gcc4/lib
[12] HASH 0x80500e8
[13] STRTAB 0x80535b8
[14] STRSZ 0x158f
[15] SYMTAB 0x8051288
[16] SYMENT 0x10
[17] CHECKSUM 0x16bb
[18] VERNEED 0x8054b48
[19] VERNEEDNUM 0x4
[20] PLTRELSZ 0x510
[21] PLTREL 0x11
[22] JMPREL 0x8054c20
[23] REL 0x8054bd8
[24] RELSZ 0x558
[25] RELENT 0x8
[26] DEBUG 0
[27] FEATURE_1 0x1 [ PARINIT ]
[28] FLAGS 0 0
[29] FLAGS_1 0 0
[30] PLTGOT 0x80c5264
That is on a Solaris box clearly. If I check to see what libs get used when I
execute gawk I see :
dclarke@titan $ ldd -fr /usr/local/bin/gawk
libsigsegv.so.2 => /usr/local/lib/libsigsegv.so.2
libc.so.1 => /usr/lib/libc.so.1
libintl.so.8 => /usr/local/lib/libintl.so.8
libiconv.so.2 => /usr/local/lib/libiconv.so.2
libsocket.so.1 => /usr/lib/libsocket.so.1
libnsl.so.1 => /usr/lib/libnsl.so.1
libdl.so.1 => /usr/lib/libdl.so.1
libm.so.1 => /usr/lib/libm.so.1
libmp.so.2 => /usr/lib/libmp.so.2
I can trace everything the runtime linker does with this :
dclarke@titan $ LD_DEBUG=files /usr/local/bin/gawk --version
07748:
07748: configuration file=/var/ld/ld.config: unable to process file
07748:
07748:
07748: file=/usr/lib/ld.so.1 [ ELF ]
07748: dynamic: 0xdfbf20bc base: 0xdfbc0000
07748: envp: 0x80479a4 auxv: 0x8047a6c
07748:
07748: file=/usr/local/bin/gawk [ ELF ]; generating link map
07748: dynamic: 0x80c550c base: 0x8050000 size: 0x82434
07748: entry: 0x8055b60 lmid: 0x0 lmco: 0xc
07748:
07748: file=/usr/local/bin/gawk; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libsigsegv.so.2; needed by /usr/local/bin/gawk
07748: file=/usr/local/lib/libsigsegv.so.2 [ ELF ]; generating link map
07748: dynamic: 0xdfa32b9c base: 0xdfa20000 size: 0x13000
07748: entry: 0xdfa20094 lmid: 0x0 lmco: 0xc
07748:
07748: file=libc.so.1; needed by /usr/local/bin/gawk
07748: file=/usr/lib/libc.so.1 [ ELF ]; generating link map
07748: dynamic: 0xdfa08940 base: 0xdf970000 size: 0xa0000
07748: entry: 0xdf98c1fc lmid: 0x0 lmco: 0xc
07748:
07748: file=libintl.so.8; needed by /usr/local/bin/gawk
07748: file=/usr/local/lib/libintl.so.8 [ ELF ]; generating link map
07748: dynamic: 0xdf95e53c base: 0xdf940000 size: 0x1f000
07748: entry: 0xdf940094 lmid: 0x0 lmco: 0xc
07748:
07748: file=libiconv.so.2; needed by /usr/local/bin/gawk
07748: file=/usr/local/lib/libiconv.so.2 [ ELF ]; generating link map
07748: dynamic: 0xdf92d1c8 base: 0xdf820000 size: 0x10e000
07748: entry: 0xdf820094 lmid: 0x0 lmco: 0xc
07748:
07748: file=libsocket.so.1; needed by /usr/local/bin/gawk
07748: file=/usr/lib/libsocket.so.1 [ ELF ]; generating link map
07748: dynamic: 0xdf81a294 base: 0xdf800000 size: 0x1b000
07748: entry: 0xdf800094 lmid: 0x0 lmco: 0xc
07748:
07748: file=libnsl.so.1; needed by /usr/local/bin/gawk
07748: file=/usr/lib/libnsl.so.1 [ ELF ]; generating link map
07748: dynamic: 0xdf7e7f64 base: 0xdf760000 size: 0x94000
07748: entry: 0xdf760094 lmid: 0x0 lmco: 0xc
07748:
07748: file=libdl.so.1; needed by /usr/local/bin/gawk
07748: file=/usr/lib/libdl.so.1 [ ELF ]; generating link map
07748: dynamic: 0xdf750094 base: 0xdf750000 size: 0x1000
07748: entry: 0xdf750094 lmid: 0x0 lmco: 0xc
07748:
07748: file=libm.so.1; needed by /usr/local/bin/gawk
07748: file=/usr/lib/libm.so.1 [ ELF ]; generating link map
07748: dynamic: 0xdf742944 base: 0xdf720000 size: 0x24000
07748: entry: 0xdf720094 lmid: 0x0 lmco: 0xc
07748:
07748: file=/usr/local/lib/libsigsegv.so.2; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libc.so.1; needed by /usr/local/lib/libsigsegv.so.2
07748:
07748: file=/usr/lib/libc.so.1; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libdl.so.1; needed by /usr/lib/libc.so.1
07748:
07748: file=/usr/local/lib/libintl.so.8; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libiconv.so.2; needed by /usr/local/lib/libintl.so.8
07748:
07748: file=libc.so.1; needed by /usr/local/lib/libintl.so.8
07748:
07748: file=/usr/local/lib/libiconv.so.2; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libc.so.1; needed by /usr/local/lib/libiconv.so.2
07748:
07748: file=/usr/lib/libsocket.so.1; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libnsl.so.1; needed by /usr/lib/libsocket.so.1
07748:
07748: file=libc.so.1; needed by /usr/lib/libsocket.so.1
07748:
07748: file=/usr/lib/libnsl.so.1; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libdl.so.1; needed by /usr/lib/libnsl.so.1
07748:
07748: file=libc.so.1; needed by /usr/lib/libnsl.so.1
07748:
07748: file=libmp.so.2; needed by /usr/lib/libnsl.so.1
07748: file=/usr/lib/libmp.so.2 [ ELF ]; generating link map
07748: dynamic: 0xdf703068 base: 0xdf6f0000 size: 0x14000
07748: entry: 0xdf6f0094 lmid: 0x0 lmco: 0xc
07748:
07748: file=/usr/lib/libdl.so.1; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=/usr/lib/libm.so.1; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libc.so.1; needed by /usr/lib/libm.so.1
07748:
07748: file=/usr/lib/libmp.so.2; analyzing [ RTLD_LAZY RTLD_GLOBAL RTLD_WORLD RTLD_NODELETE ]
07748:
07748: file=libc.so.1; needed by /usr/lib/libmp.so.2
07748:
07748: file=/usr/lib/libdl.so.1; filter for /usr/lib/ld.so.1
07748:
07748: file=/usr/lib/ld.so.1; filtered by /usr/lib/libdl.so.1
07748:
07748:
07748:
07748:
07748:
07748:
07748: transferring control: /usr/local/bin/gawk
07748:
GNU Awk 4.0.2
Copyright (C) 1989, 1991-2012 Free Software Foundation.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see http://www.gnu.org/licenses/.
07748:
07748:
07748:
07748:
07748:
In this way I can build binaries with confidence and know where the libs
are being pulled from to execute a given function. Am I correct thus far?
Now I switch over to a linux system and I also try to ensure that I have
a RPATH/RUNPATH setup within any binary that goes into a non-standard
place like /usr/local/bin thus :
dclarke@phobos:/usr/local/build$ /usr/local/bin/greadelf -dh /usr/local/bin/gawk
ELF Header:
Magic: 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: EXEC (Executable file)
Machine: Intel 80386
Version: 0x1
Entry point address: 0x804eb60
Start of program headers: 52 (bytes into file)
Start of section headers: 718352 (bytes into file)
Flags: 0x0
Size of this header: 52 (bytes)
Size of program headers: 32 (bytes)
Number of program headers: 8
Size of section headers: 40 (bytes)
Number of section headers: 40
Section header string table index: 37
Dynamic section at offset 0x660d4 contains 25 entries:
Tag Type Name/Value
0x00000001 (NEEDED) Shared library: [libsigsegv.so.2]
0x00000001 (NEEDED) Shared library: [libc.so.6]
0x00000001 (NEEDED) Shared library: [libdl.so.2]
0x00000001 (NEEDED) Shared library: [libm.so.6]
0x0000000f (RPATH) Library rpath: [/usr/local/lib]
0x0000000c (INIT) 0x804e0d4
0x0000000d (FINI) 0x80a211c
0x00000004 (HASH) 0x804818c
0x6ffffef5 (GNU_HASH) 0x8049274
0x00000005 (STRTAB) 0x804c1ec
0x00000006 (SYMTAB) 0x8049efc
0x0000000a (STRSZ) 5266 (bytes)
0x0000000b (SYMENT) 16 (bytes)
0x00000015 (DEBUG) 0x0
0x00000003 (PLTGOT) 0x80af1c8
0x00000002 (PLTRELSZ) 1312 (bytes)
0x00000014 (PLTREL) REL
0x00000017 (JMPREL) 0x804dbb4
0x00000011 (REL) 0x804db8c
0x00000012 (RELSZ) 40 (bytes)
0x00000013 (RELENT) 8 (bytes)
0x6ffffffe (VERNEED) 0x804dadc
0x6fffffff (VERNEEDNUM) 3
0x6ffffff0 (VERSYM) 0x804d67e
0x00000000 (NULL) 0x0
I can try to see what libs are being used when I execute gawk like so :
dclarke@phobos:/usr/local/build$ LD_DEBUG=files /usr/local/bin/gawk --version
5199:
5199: file=libsigsegv.so.2 [0]; needed by /usr/local/bin/gawk [0]
5199: file=libsigsegv.so.2 [0]; generating link map
5199: dynamic: 0xb773fe0c base: 0xb773d000 size: 0x00002f70
5199: entry: 0xb773d990 phdr: 0xb773d034 phnum: 5
5199:
5199:
5199: file=libc.so.6 [0]; needed by /usr/local/bin/gawk [0]
5199: file=libc.so.6 [0]; generating link map
5199: dynamic: 0xb7727d7c base: 0xb75e5000 size: 0x00146968
5199: entry: 0xb75fbe00 phdr: 0xb75e5034 phnum: 10
5199:
5199:
5199: file=libdl.so.2 [0]; needed by /usr/local/bin/gawk [0]
5199: file=libdl.so.2 [0]; generating link map
5199: dynamic: 0xb75e2ed0 base: 0xb75e0000 size: 0x00003078
5199: entry: 0xb75e0a40 phdr: 0xb75e0034 phnum: 8
5199:
5199:
5199: file=libm.so.6 [0]; needed by /usr/local/bin/gawk [0]
5199: file=libm.so.6 [0]; generating link map
5199: dynamic: 0xb75deef0 base: 0xb75ba000 size: 0x00025080
5199: entry: 0xb75bd460 phdr: 0xb75ba034 phnum: 9
5199:
5199:
5199: calling init: /lib/i686/cmov/libc.so.6
5199:
5199:
5199: calling init: /lib/i686/cmov/libm.so.6
5199:
5199:
5199: calling init: /lib/i686/cmov/libdl.so.2
5199:
5199:
5199: calling init: /usr/local/lib/libsigsegv.so.2
5199:
5199:
5199: initialize program: /usr/local/bin/gawk
5199:
5199:
5199: transferring control: /usr/local/bin/gawk
5199:
GNU Awk 4.0.2
Copyright (C) 1989, 1991-2012 Free Software Foundation.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see http://www.gnu.org/licenses/.
5199:
5199: calling fini: /usr/local/bin/gawk [0]
5199:
5199:
5199: calling fini: /usr/local/lib/libsigsegv.so.2 [0]
5199:
5199:
5199: calling fini: /lib/i686/cmov/libdl.so.2 [0]
5199:
5199:
5199: calling fini: /lib/i686/cmov/libm.so.6 [0]
5199:
5199:
5199: calling fini: /lib/i686/cmov/libc.so.6 [0]
5199:
There I see libm and libc and libdl all found within /lib. What if I
were to be sneaky and slide a modified libc into /usr/local/lib ?
Consider this spooky looking thing :
dclarke@phobos:/usr/local/lib$ ldd -r /usr/local/bin/gawk
linux-gate.so.1 => (0xb77cb000)
libsigsegv.so.2 => /usr/local/lib/libsigsegv.so.2 (0xb77c6000)
libc.so.6 => /usr/local/lib/libc.so.6 (0xb767f000)
libdl.so.2 => /usr/local/lib/libdl.so.2 (0xb767a000)
libm.so.6 => /usr/local/lib/libm.so.6 (0xb7654000)
/lib/ld-linux.so.2 (0xb77cc000)
There I have placed a libc.so.6 within /usr/local/lib and if I were sneaky
I could make that a hand crafted lib that can do all manner of bad things.
I think the implications are just, well spooky :
dclarke@phobos:/usr/local/lib$ which gcc
/usr/local/gcc4/bin/gcc
dclarke@phobos:/usr/local/lib$ ldd /usr/local/gcc4/bin/gcc
linux-gate.so.1 => (0xb7745000)
libiconv.so.2 => /usr/local/lib/libiconv.so.2 (0xb765c000)
libm.so.6 => /usr/local/lib/libm.so.6 (0xb7636000)
libc.so.6 => /usr/local/lib/libc.so.6 (0xb74ee000)
/lib/ld-linux.so.2 (0xb7746000)
dclarke@phobos:/usr/local/lib$ /usr/local/gcc4/bin/gcc --version
gcc (Blastwave.org Inc. Sun Apr 28 08:01:32 GMT 2013) 4.7.3
Copyright (C) 2012 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
So I try to force binaries to use libs within the destination prefix /usr/local and
then ensure that there is a RPATH/RUNPATH in the elf headers that points
to that prefix also. The downside is that I just don't know of a way to really
ensure that libs like libc and libm *always* come from the vendor OS and
not from some hacked version within /usr/local/lib.
Sorry if I went way off topic. Perhaps into the weeds a bit, but I always have
a somewhat curious opinion of binaries that are not from the OS vendor and
wonder what else they may be doing, and how, and why. I just don't know
how else to say it, and am possibly making a real mess of this. The libs needed
by a given binary should be somehow electric fence protected, possibly even
a sha256 hash in the elf header that clearly identifies it is correct for the binary.
Long long story short, my build of GCC 4.8.x is messy because the testsuite runs
were using libs from /usr/local/lib and /usr/local/gcc4/lib which all are from a
previous GCC 4.7.3 install.
So, perhaps some wrong thinking on my part.
dc
