elf_backend_section_flags and _bfd_elf_init_private_section_data
Alan Modra
amodra@gmail.com
Mon Mar 2 01:03:00 GMT 2020
I was looking at elf_backend_section_flags as a means of setting
SEC_SMALL_DATA for .sdata, .sbss and the like, and condidered adding
an asection* parameter to access the section name easily before
realising that hdr->bfd_section of course makes the section
available. So no new parameter needed. In fact the flagword*
parameter isn't needed either, so out it goes.
The patch also tidies some horrible code in _bfd_elf_new_section_hook
that can change whether known ABI sections have sh_type and sh_flags
set up depending on which of the bfd_make_section functions is used.
(Some of those set section flags before _bfd_elf_new_section_hook is
called, others leave the flags zero.) The function also had some
hacks for .init_array and .fini_array to affect how
_bfd_elf_init_private_section_data behaved for those sections. It's
cleaner to do that in _bfd_elf_init_private_section_data. So that all
goes and we now init sh_type and sh_flags for all known ABI sections
in _bfd_elf_new_section_hook. _bfd_elf_init_private_section_data is
changed to suit, and now doesn't just single out SHT_INIT_ARRAY and
SHT_FINI_ARRAY but rather any of the special section types.
The _bfd_elf_new_section_hook change resulting in
+FAIL: ld-aarch64/erratum835769-843419
exposing some errors in the aarch64 backend. elfNN_aarch64_size_stubs
should not be looking at linker created sections in the stub bfd. Nor
should code like "symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr" be
run without first checking that input_bfd is ELF.
* elf-bfd.h (elf_backend_section_flags): Remove flagword* param.
* elf.c (_bfd_elf_make_section_from_shdr): Set section flags before
calling elf_backend_section_flags with adjusted params. Use
newsect->flags past that point.
(_bfd_elf_new_section_hook): Always set sh_type and sh_flags for
special sections.
(_bfd_elf_init_private_section_data): Allow normal sh_type sections
to have their type overridden, and all sh_flags but processor and
os specific.
* elf32-arm.c (elf32_arm_section_flags): Adjust for changed params.
* elf32-mep.c (mep_elf_section_flags): Likewise.
* elf32-nios2.c (nios2_elf32_section_flags): Likewise.
* elf64-alpha.c (elf64_alpha_section_flags): Likewise.
* elf64-ia64-vms.c (elf64_ia64_section_flags): Likewise.
* elfnn-ia64.c (elfNN_ia64_section_flags): Likewise.
* elfnn-aarch64.c (elfNN_aarch64_size_stubs): Exclude the linker
stub BFD and non-aarch64 input files when scanning for stubs.
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index b930761363..61e733f068 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -955,7 +955,7 @@ struct elf_backend_data
/* A function to convert machine dependent ELF section header flags to
BFD internal section header flags. */
bfd_boolean (*elf_backend_section_flags)
- (flagword *, const Elf_Internal_Shdr *);
+ (const Elf_Internal_Shdr *);
/* A function that returns a struct containing ELF section flags and
type for the given BFD section. */
diff --git a/bfd/elf.c b/bfd/elf.c
index 265fc87ad5..fcd84d2d17 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -1114,14 +1114,14 @@ _bfd_elf_make_section_from_shdr (bfd *abfd,
&& elf_next_in_group (newsect) == NULL)
flags |= SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD;
+ if (!bfd_set_section_flags (newsect, flags))
+ return FALSE;
+
bed = get_elf_backend_data (abfd);
if (bed->elf_backend_section_flags)
- if (! bed->elf_backend_section_flags (&flags, hdr))
+ if (!bed->elf_backend_section_flags (hdr))
return FALSE;
- if (!bfd_set_section_flags (newsect, flags))
- return FALSE;
-
/* We do not parse the PT_NOTE segments as we are interested even in the
separate debug info files which may have the segments offsets corrupted.
PT_NOTEs from the core files are currently not parsed using BFD. */
@@ -1137,7 +1137,7 @@ _bfd_elf_make_section_from_shdr (bfd *abfd,
free (contents);
}
- if ((flags & SEC_ALLOC) != 0)
+ if ((newsect->flags & SEC_ALLOC) != 0)
{
Elf_Internal_Phdr *phdr;
unsigned int i, nload;
@@ -1163,7 +1163,7 @@ _bfd_elf_make_section_from_shdr (bfd *abfd,
|| phdr->p_type == PT_TLS)
&& ELF_SECTION_IN_SEGMENT (hdr, phdr))
{
- if ((flags & SEC_LOAD) == 0)
+ if ((newsect->flags & SEC_LOAD) == 0)
newsect->lma = (phdr->p_paddr
+ hdr->sh_addr - phdr->p_vaddr);
else
@@ -1191,7 +1191,7 @@ _bfd_elf_make_section_from_shdr (bfd *abfd,
/* Compress/decompress DWARF debug sections with names: .debug_* and
.zdebug_*, after the section flags is set. */
- if ((flags & SEC_DEBUGGING)
+ if ((newsect->flags & SEC_DEBUGGING)
&& ((name[1] == 'd' && name[6] == '_')
|| (name[1] == 'z' && name[7] == '_')))
{
@@ -2900,28 +2900,13 @@ _bfd_elf_new_section_hook (bfd *abfd, asection *sec)
bed = get_elf_backend_data (abfd);
sec->use_rela_p = bed->default_use_rela_p;
- /* When we read a file, we don't need to set ELF section type and
- flags. They will be overridden in _bfd_elf_make_section_from_shdr
- anyway. We will set ELF section type and flags for all linker
- created sections. If user specifies BFD section flags, we will
- set ELF section type and flags based on BFD section flags in
- elf_fake_sections. Special handling for .init_array/.fini_array
- output sections since they may contain .ctors/.dtors input
- sections. We don't want _bfd_elf_init_private_section_data to
- copy ELF section type from .ctors/.dtors input sections. */
- if (abfd->direction != read_direction
- || (sec->flags & SEC_LINKER_CREATED) != 0)
+ /* Set up ELF section type and flags for newly created sections, if
+ there is an ABI mandated section. */
+ ssect = (*bed->get_sec_type_attr) (abfd, sec);
+ if (ssect != NULL)
{
- ssect = (*bed->get_sec_type_attr) (abfd, sec);
- if (ssect != NULL
- && (!sec->flags
- || (sec->flags & SEC_LINKER_CREATED) != 0
- || ssect->type == SHT_INIT_ARRAY
- || ssect->type == SHT_FINI_ARRAY))
- {
- elf_section_type (sec) = ssect->type;
- elf_section_flags (sec) = ssect->attr;
- }
+ elf_section_type (sec) = ssect->type;
+ elf_section_flags (sec) = ssect->attr;
}
return _bfd_generic_new_section_hook (abfd, sec);
@@ -7757,10 +7742,19 @@ _bfd_elf_init_private_section_data (bfd *ibfd,
BFD_ASSERT (elf_section_data (osec) != NULL);
- /* For objcopy and relocatable link, don't copy the output ELF
- section type from input if the output BFD section flags have been
- set to something different. For a final link allow some flags
- that the linker clears to differ. */
+ /* If this is a known ABI section, ELF section type and flags may
+ have been set up when OSEC was created. For normal sections we
+ allow the user to override the type and flags other than
+ SHF_MASKOS and SHF_MASKPROC. */
+ if (elf_section_type (osec) == SHT_PROGBITS
+ || elf_section_type (osec) == SHT_NOTE
+ || elf_section_type (osec) == SHT_NOBITS)
+ elf_section_type (osec) = SHT_NULL;
+ /* For objcopy and relocatable link, copy the ELF section type from
+ the input file if the BFD section flags are the same. (If they
+ are different the user may be doing something like
+ "objcopy --set-section-flags .text=alloc,data".) For a final
+ link allow some flags that the linker clears to differ. */
if (elf_section_type (osec) == SHT_NULL
&& (osec->flags == isec->flags
|| (final_link
@@ -7769,8 +7763,8 @@ _bfd_elf_init_private_section_data (bfd *ibfd,
elf_section_type (osec) = elf_section_type (isec);
/* FIXME: Is this correct for all OS/PROC specific flags? */
- elf_section_flags (osec) |= (elf_section_flags (isec)
- & (SHF_MASKOS | SHF_MASKPROC));
+ elf_section_flags (osec) = (elf_section_flags (isec)
+ & (SHF_MASKOS | SHF_MASKPROC));
/* Copy sh_info from input for mbind section. */
if ((elf_tdata (ibfd)->has_gnu_osabi & elf_gnu_osabi_mbind) != 0
diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c
index e9d93cc3b8..c899aeb8f6 100644
--- a/bfd/elf32-arm.c
+++ b/bfd/elf32-arm.c
@@ -20230,10 +20230,10 @@ elf32_arm_get_synthetic_symtab (bfd *abfd,
}
static bfd_boolean
-elf32_arm_section_flags (flagword *flags, const Elf_Internal_Shdr * hdr)
+elf32_arm_section_flags (const Elf_Internal_Shdr *hdr)
{
if (hdr->sh_flags & SHF_ARM_PURECODE)
- *flags |= SEC_ELF_PURECODE;
+ hdr->bfd_section->flags |= SEC_ELF_PURECODE;
return TRUE;
}
diff --git a/bfd/elf32-mep.c b/bfd/elf32-mep.c
index 14a6d22621..c5775de649 100644
--- a/bfd/elf32-mep.c
+++ b/bfd/elf32-mep.c
@@ -717,10 +717,10 @@ mep_elf_object_p (bfd * abfd)
}
static bfd_boolean
-mep_elf_section_flags (flagword * flags, const Elf_Internal_Shdr * hdr)
+mep_elf_section_flags (const Elf_Internal_Shdr *hdr)
{
if (hdr->sh_flags & SHF_MEP_VLIW)
- * flags |= SEC_MEP_VLIW;
+ hdr->bfd_section->flags |= SEC_MEP_VLIW;
return TRUE;
}
diff --git a/bfd/elf32-nios2.c b/bfd/elf32-nios2.c
index 17e97bca5a..2fcfe6fd6c 100644
--- a/bfd/elf32-nios2.c
+++ b/bfd/elf32-nios2.c
@@ -4539,10 +4539,10 @@ nios2_elf32_relocate_section (bfd *output_bfd,
/* Implement elf-backend_section_flags:
Convert NIOS2 specific section flags to bfd internal section flags. */
static bfd_boolean
-nios2_elf32_section_flags (flagword *flags, const Elf_Internal_Shdr *hdr)
+nios2_elf32_section_flags (const Elf_Internal_Shdr *hdr)
{
if (hdr->sh_flags & SHF_NIOS2_GPREL)
- *flags |= SEC_SMALL_DATA;
+ hdr->bfd_section->flags |= SEC_SMALL_DATA;
return TRUE;
}
diff --git a/bfd/elf64-alpha.c b/bfd/elf64-alpha.c
index ed18202b71..9d2d7f1d4d 100644
--- a/bfd/elf64-alpha.c
+++ b/bfd/elf64-alpha.c
@@ -1180,10 +1180,10 @@ elf64_alpha_section_from_shdr (bfd *abfd,
/* Convert Alpha specific section flags to bfd internal section flags. */
static bfd_boolean
-elf64_alpha_section_flags (flagword *flags, const Elf_Internal_Shdr *hdr)
+elf64_alpha_section_flags (const Elf_Internal_Shdr *hdr)
{
if (hdr->sh_flags & SHF_ALPHA_GPREL)
- *flags |= SEC_SMALL_DATA;
+ hdr->bfd_section->flags |= SEC_SMALL_DATA;
return TRUE;
}
diff --git a/bfd/elf64-ia64-vms.c b/bfd/elf64-ia64-vms.c
index 636d7897ee..d40fa4277a 100644
--- a/bfd/elf64-ia64-vms.c
+++ b/bfd/elf64-ia64-vms.c
@@ -822,11 +822,10 @@ is_unwind_section_name (bfd *abfd ATTRIBUTE_UNUSED, const char *name)
flag. */
static bfd_boolean
-elf64_ia64_section_flags (flagword *flags,
- const Elf_Internal_Shdr *hdr)
+elf64_ia64_section_flags (const Elf_Internal_Shdr *hdr)
{
if (hdr->sh_flags & SHF_IA_64_SHORT)
- *flags |= SEC_SMALL_DATA;
+ hdr->bfd_section->flags |= SEC_SMALL_DATA;
return TRUE;
}
diff --git a/bfd/elfnn-aarch64.c b/bfd/elfnn-aarch64.c
index 35dd8ab167..ba3ad45468 100644
--- a/bfd/elfnn-aarch64.c
+++ b/bfd/elfnn-aarch64.c
@@ -4313,9 +4313,15 @@ elfNN_aarch64_size_stubs (bfd *output_bfd,
for (input_bfd = info->input_bfds;
input_bfd != NULL; input_bfd = input_bfd->link.next)
- if (!_bfd_aarch64_erratum_835769_scan (input_bfd, info,
- &num_erratum_835769_fixes))
- return FALSE;
+ {
+ if (!is_aarch64_elf (input_bfd)
+ || (input_bfd->flags & BFD_LINKER_CREATED) != 0)
+ continue;
+
+ if (!_bfd_aarch64_erratum_835769_scan (input_bfd, info,
+ &num_erratum_835769_fixes))
+ return FALSE;
+ }
_bfd_aarch64_resize_stubs (htab);
(*htab->layout_sections_again) ();
@@ -4331,6 +4337,10 @@ elfNN_aarch64_size_stubs (bfd *output_bfd,
{
asection *section;
+ if (!is_aarch64_elf (input_bfd)
+ || (input_bfd->flags & BFD_LINKER_CREATED) != 0)
+ continue;
+
for (section = input_bfd->sections;
section != NULL;
section = section->next)
@@ -4353,6 +4363,10 @@ elfNN_aarch64_size_stubs (bfd *output_bfd,
asection *section;
Elf_Internal_Sym *local_syms = NULL;
+ if (!is_aarch64_elf (input_bfd)
+ || (input_bfd->flags & BFD_LINKER_CREATED) != 0)
+ continue;
+
/* We'll need the symbol table in a second. */
symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
if (symtab_hdr->sh_info == 0)
diff --git a/bfd/elfnn-ia64.c b/bfd/elfnn-ia64.c
index 1df2aa842c..208b85df90 100644
--- a/bfd/elfnn-ia64.c
+++ b/bfd/elfnn-ia64.c
@@ -942,11 +942,10 @@ elfNN_ia64_section_from_shdr (bfd *abfd,
flag. */
static bfd_boolean
-elfNN_ia64_section_flags (flagword *flags,
- const Elf_Internal_Shdr *hdr)
+elfNN_ia64_section_flags (const Elf_Internal_Shdr *hdr)
{
if (hdr->sh_flags & SHF_IA_64_SHORT)
- *flags |= SEC_SMALL_DATA;
+ hdr->bfd_section->flags |= SEC_SMALL_DATA;
return TRUE;
}
--
Alan Modra
Australia Development Lab, IBM
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