commit 825e48c4e942e3cbdab1b75c04b8c014867d66ab

Author: Milian Wolff <milian.wolff@kdab.com>

Date:   Mon Oct 29 16:21:26 2018 +0100

    Also find CFI in sections of type SHT_X86_64_UNWIND

    On my system with g++ (GCC) 8.2.1 20180831 with GNU gold (GNU Binutils

    2.31.1) 1.16, the .eh_frame section does not have type PROGBITS

    but rather is using X86_64_UNWIND nowadays:

    ```

    $ echo "int main(){ return 0; }" > test.c

    $ gcc test.c

    $ readelf --sections a.out | grep .eh_frame

      [14] .eh_frame         X86_64_UNWIND    0000000000000670  00000670

      [15] .eh_frame_hdr     X86_64_UNWIND    0000000000000724  00000724

    ```

    Without this patch, libdw refuses to use the available unwind

    information, leading to broken backtraces while unwinding. With the

    patch applied, unwinding works once more in such situations.

    Signed-off-by: Milian Wolff <milian.wolff@kdab.com>

    Signed-off-by: Mark Wielaard <mark@klomp.org>

    Tested-by: Milian Wolff <milian.wolff@kdab.com>

diff --git a/libdw/dwarf_getcfi_elf.c b/libdw/dwarf_getcfi_elf.c

index 315cc02..adcaea0 100644

--- a/libdw/dwarf_getcfi_elf.c

+++ b/libdw/dwarf_getcfi_elf.c

@@ -298,7 +298,7 @@ getcfi_shdr (Elf *elf, const GElf_Ehdr *ehdr)

 	    }

 	  else if (!strcmp (name, ".eh_frame"))

 	    {

-	      if (shdr->sh_type == SHT_PROGBITS)

+	      if (shdr->sh_type != SHT_NOBITS)

 		return getcfi_scn_eh_frame (elf, ehdr, scn, shdr,

 					    hdr_scn, hdr_vaddr);

 	      else

commit 4b0342b85b5b1a3d3636e06e3b5320954828dfb1

Author: Mark Wielaard <mark@klomp.org>

Date:   Tue Nov 6 12:01:25 2018 +0100

    backends: Add x86_64 section_type_name for SHT_X86_64_UNWIND.

    Makes sure that eu-readelf and eu-elflint recognize and show the

    x86_64 specific section type correctly.

    Signed-off-by: Mark Wielaard <mark@klomp.org>

    Tested-by: Milian Wolff <milian.wolff@kdab.com>

diff --git a/backends/x86_64_init.c b/backends/x86_64_init.c

index adfa479..49f6c6c 100644

--- a/backends/x86_64_init.c

+++ b/backends/x86_64_init.c

@@ -1,5 +1,5 @@

 /* Initialization of x86-64 specific backend library.

-   Copyright (C) 2002-2009, 2013 Red Hat, Inc.

+   Copyright (C) 2002-2009, 2013, 2018 Red Hat, Inc.

    Copyright (C) H.J. Lu <hjl.tools@gmail.com>, 2015.

    This file is part of elfutils.

    Written by Ulrich Drepper <drepper@redhat.com>, 2002.

@@ -55,6 +55,7 @@ x86_64_init (Elf *elf __attribute__ ((unused)),

   eh->name = "AMD x86-64";

   x86_64_init_reloc (eh);

   HOOK (eh, reloc_simple_type);

+  HOOK (eh, section_type_name);

   if (eh->class == ELFCLASS32)

     eh->core_note = x32_core_note;

   else

diff --git a/backends/x86_64_symbol.c b/backends/x86_64_symbol.c

index e07b180..98457bc 100644

--- a/backends/x86_64_symbol.c

+++ b/backends/x86_64_symbol.c

@@ -1,5 +1,5 @@

 /* x86_64 specific symbolic name handling.

-   Copyright (C) 2002, 2005 Red Hat, Inc.

+   Copyright (C) 2002, 2005, 2018 Red Hat, Inc.

    This file is part of elfutils.

    Written by Ulrich Drepper <drepper@redhat.com>, 2002.

@@ -59,3 +59,15 @@ x86_64_reloc_simple_type (Ebl *ebl __attribute__ ((unused)), int type,

       return ELF_T_NUM;

     }

 }

+

+/* Return symbolic representation of section type.  */

+const char *

+x86_64_section_type_name (int type,

+			  char *buf __attribute__ ((unused)),

+			  size_t len __attribute__ ((unused)))

+{

+  if (type == SHT_X86_64_UNWIND)

+    return "X86_64_UNWIND";

+

+  return NULL;

+}

commit 22ec8efc1dd87cdc7892523457eb55990b967224

Author: Mark Wielaard <mark@klomp.org>

Date:   Sat Nov 10 23:33:03 2018 +0100

    elflint: Allow PT_GNU_EH_FRAME segment to match SHT_X86_64_UNWIND section.

    The gold linker might generate an .eh_frame_hdr with a SHT_X86_64_UNWIND

    type instead of a SHT_PROGBITS type.

    Signed-off-by: Mark Wielaard <mark@klomp.org>

diff --git a/src/elflint.c b/src/elflint.c

index 184ca12..810c8bd 100644

--- a/src/elflint.c

+++ b/src/elflint.c

@@ -4633,8 +4633,10 @@ program header offset in ELF header and PHDR entry do not match"));

 	      any = true;

 	      shdr = gelf_getshdr (scn, &shdr_mem);

 	      if (shdr != NULL

-		  && shdr->sh_type == (is_debuginfo

-				       ? SHT_NOBITS : SHT_PROGBITS)

+		  && ((is_debuginfo && shdr->sh_type == SHT_NOBITS)

+		      || (! is_debuginfo

+			  && (shdr->sh_type == SHT_PROGBITS

+			      || shdr->sh_type == SHT_X86_64_UNWIND)))

 		  && elf_strptr (ebl->elf, shstrndx, shdr->sh_name) != NULL

 		  && ! strcmp (".eh_frame_hdr",

 			       elf_strptr (ebl->elf, shstrndx, shdr->sh_name)))