Re: ld fix for STB_GNU_UNIQUE PR10549

[Mark Wielaard <mjw at redhat dot com>]

On Thu, 2011-04-07 at 13:03 -0700, H.J. Lu wrote:
> On Thu, Apr 7, 2011 at 1:01 PM, Mark Wielaard <mjw@redhat.com> wrote:
> > This is the ld part of the fix for PR 10549. Nick Clifton already fixed
> > the assembler part. If STB_GNU_UNIQUE is used ELFOSABI_LINUX should be
> > set.
> >
> > 2011-04-07  Mark Wielaard  <mjw@redhat.com>
> >
> >    PR 10549
> >    * elf-bfd.h (has_ifunc_symbols): Renamed to has_gnu_symbols.
> >    (has_gnu_symbols): Renamed from has_ifunc_symbols.
> >    * bfd/elf.c (_bfd_elf_set_osabi): Use new has_gnu_symbols name.
> >    * bfd/elf32-arm.c (elf32_arm_add_symbol_hook): Set has_gnu_symbols
> >    also if STB_GNU_UNIQUE symbol binding was seen.
> >    * bfd/elf32-i386.c (elf_i386_add_symbol_hook): Likewise.
> >    * bfd/elf32-ppc.c (ppc_elf_add_symbol_hook): Likewise.
> >    * bfd/elf32-sparc.c (elf32_sparc_add_symbol_hook): Likewise.
> >    * bfd/elf64-ppc.c (ppc64_elf_add_symbol_hook): Likewise.
> >    * bfd/elf64-sparc.c (elf64_sparc_add_symbol_hook): Likewise.
> >    * bfd/elf64-x86-64.c (elf_x86_64_add_symbol_hook): Likewise.
> >
> > Build and tested on x86_64 GNU/Linux with --enable-targets=all.
> >
> > If this is good, could someone commit it for me?
> 
> Please include the testcase from
> 
> http://sourceware.org/bugzilla/show_bug.cgi?id=10549

OK, I wrapped it in an expect test based on ifunc.exp slightly adapted
to check for UNIQUE instead.

ld/testsuite/ChangeLog
2011-04-08  Mark Wielaard  <mjw@redhat.com>

        * ld-unique: New directory.
        * ld-unique/unique.exp: New file: Run the UNIQUE tests.
        * ld-ifunc/unique.s: New test file.

This fails without my patch and passes with the patch applied.

Please commit it together with the original patch if it is OK.

Thanks,

Mark

diff --git a/ld/testsuite/ld-unique/unique.exp b/ld/testsuite/ld-unique/unique.exp
new file mode 100644
index 0000000..c828aad
--- /dev/null
+++ b/ld/testsuite/ld-unique/unique.exp
@@ -0,0 +1,144 @@
+# Expect script for linker support of STB_GNU_UNIQUE symbols
+#
+#   Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
+#   Contributed by Red Hat.
+#
+# This file is part of the GNU Binutils.
+#
+# 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, write to the Free Software
+# Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+# MA 02110-1301, USA.
+#
+# Written by Nick Clifton <nickc@redhat.com>
+# Adapted for unique checking by Mark J. Wielaard <mjw@redhat.com>
+
+
+# STB_GNU_UNIQUE support has only been implemented for the ix86, x86_64,
+# arm, powerpc, and sparc so far.
+if {!(([istarget "i?86-*-*"]
+       || [istarget "x86_64-*-*"]
+       || [istarget "arm-*-*"]
+       || [istarget "powerpc*-*-*"]
+       || [istarget "sparc*-*-*"])
+      && ([istarget "*-*-elf*"]
+	  || (([istarget "*-*-linux*"]
+	       || [istarget "*-*-gnu*"])
+	      && ![istarget "*-*-*aout*"]
+	      && ![istarget "*-*-*oldld*"]))) } {
+    verbose "UNIQUE tests not run - target does not support UNIQUE"
+    return
+}
+
+# We need a native system.  FIXME: Strictly speaking this
+# is not true, we just need to know how to create a fully
+# linked executable, including the C and Z libraries, using
+# the linker that is under test.
+if ![isnative] {
+    verbose "UNIQUE tests not run - not a native toolchain"
+    return
+}
+
+# We need a working compiler.  (Strictly speaking this is
+# not true, we could use target specific assembler files).
+if { [which $CC] == 0 } {
+    verbose "UNIQUE tests not run - no compiler available"
+    return
+}
+
+# A procedure to check the OS/ABI field in the ELF header of a binary file.
+proc check_osabi { binary_file expected_osabi } {
+    global READELF
+    global READELFFLAGS
+
+    catch "exec $READELF $READELFFLAGS --file-header $binary_file > readelf.out" got
+
+    if ![string match "" $got] then {
+	verbose "proc check_osabi: Readelf produced unexpected out processing $binary_file: $got"
+	return 0
+    }
+
+    if { ![regexp "\n\[ \]*OS/ABI:\[ \]*(.+)\n\[ \]*ABI" \
+	   [file_contents readelf.out] nil osabi] } {
+	verbose "proc check_osabi: Readelf failed to extract an ELF header from $binary_file"
+	return 0
+    }
+
+    if { $osabi == $expected_osabi } {
+	return 1
+    }
+
+    verbose "Expected OSABI: $expected_osabi, Obtained osabi: $osabi"
+    
+    return 0
+}
+
+# A procedure to confirm that a file contains the UNIQUE symbol.
+# Returns -1 upon error, 0 if the symbol was not found and 1 if it was found.
+proc contains_unique_symbol { binary_file } {
+    global READELF
+    global READELFFLAGS
+
+    catch "exec $READELF $READELFFLAGS --symbols $binary_file > readelf.out" got
+
+    if ![string match "" $got] then {
+	verbose "proc contains_unique_symbol: Readelf produced unexpected out processing $binary_file: $got"
+	return -1
+    }
+
+    # Look for a line like this:
+    #    54: 0000000000400474     4 OBJECT  UNIQUE DEFAULT   13 a
+
+    if { ![regexp ".*\[ \]*OBJECT\[ \]+UNIQUE\[ \]+DEFAULT\[ \]+\[UND0-9\]+\[ \]+a\n" [file_contents readelf.out]] } {
+	return 0
+    }
+
+    return 1
+}
+
+set fails 0
+
+# create executable containing unique symbol
+if ![ld_compile "$CC -c" "$srcdir/$subdir/unique.s" "tmpdir/unique.o"] {
+    fail "Could not create a unique object"
+    set fails [expr $fails + 1]
+}
+if ![default_ld_link $ld "tmpdir/unique_prog" "tmpdir/unique.o"] {
+    fail "Could not link a unique executable"
+    set fails [expr $fails + 1]
+}
+
+if { $fails != 0 } {
+    return
+}
+
+# check the executable
+if {! [check_osabi tmpdir/unique_prog {UNIX - Linux}]} {
+    fail "Executable containing unique does not have an OS/ABI field of LINUX"
+    set fails [expr $fails + 1]
+}
+
+if {[contains_unique_symbol tmpdir/unique_prog] != 1} {
+    fail "Executable containing unique does not contain an UNIQUE symbol"
+    set fails [expr $fails + 1]
+}
+
+if { $fails == 0 } {
+  pass "Checking unique binary"
+}
+
+# Clean up, unless we are being verbose, in which case we leave the files available.
+if { $verbose < 1 } {
+    remote_file host delete "tmpdir/unique.o"
+    remote_file host delete "tmpdir/unique_prog"
+}
diff --git a/ld/testsuite/ld-unique/unique.s b/ld/testsuite/ld-unique/unique.s
new file mode 100644
index 0000000..9b0593c
--- /dev/null
+++ b/ld/testsuite/ld-unique/unique.s
@@ -0,0 +1,8 @@
+	.type a, @gnu_unique_object
+a:	.long 0
+	.size a, .-a
+
+        .type main,"function"
+        .global main
+main:
+        .long 0