PATCH: PR ld/3223/3267: Properly handle empty output section
H. J. Lu
hjl@lucon.org
Tue Sep 26 23:28:00 GMT 2006
This patch restores the old behavior of output section discarding. It
also documents that non-constant output section address will be
ignored when it is discarded.
H.J.
---
bfd/
2006-09-26 H.J. Lu <hongjiu.lu@intel.com>
PR ld/3223
PR ld/3267
* elf.c (assign_file_positions_for_non_load_sections): Don't
warn zero size allocated sections.
ld/
2006-09-26 H.J. Lu <hongjiu.lu@intel.com>
PR ld/3223
PR ld/3267
* ld.texinfo: Updated Output Section Discarding.
* ldlang.h (lang_output_section_statement_type): Add ignored_vma
and section_relative_symbol.
* ldlang.c (strip_excluded_output_sections): Don't strip a
section with a symbol relative to it. Set ignored_vma to TRUE
if address of an empty output section isn't set to a constant.
(lang_size_sections_1): Mark if an output section has a symbol
symbol relative to it. Check ignored_vma for updating "dot",
instead of ignored.
(lang_do_assignments_1): Check ignored_vma for updating "dot",
instead of ignored.
ld/testsuite/
2006-09-26 H.J. Lu <hongjiu.lu@intel.com>
PR ld/3223
PR ld/3267
* ld-scripts/empty-address-1.d: New file.
* ld-scripts/empty-address-1.s: Likewise.
* ld-scripts/empty-address-1.t: Likewise.
* ld-scripts/empty-address-2.s: Likewise.
* ld-scripts/empty-address-2a.d: Likewise.
* ld-scripts/empty-address-2a.t: Likewise.
* ld-scripts/empty-address-2b.d: Likewise.
* ld-scripts/empty-address-2b.t: Likewise.
* ld-scripts/empty-address-3.s: Likewise.
* ld-scripts/empty-address-3a.d: Likewise.
* ld-scripts/empty-address-3a.t: Likewise.
* ld-scripts/empty-address-3b.d: Likewise.
* ld-scripts/empty-address-3b.t: Likewise.
* ld-scripts/empty-address-3c.d: Likewise.
* ld-scripts/empty-address-3c.t: Likewise.
* ld-scripts/empty-address.exp: Likewise.
--- binutils/bfd/elf.c.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/bfd/elf.c 2006-09-26 15:07:38.000000000 -0700
@@ -4662,12 +4662,13 @@ assign_file_positions_for_non_load_secti
hdr->sh_offset = hdr->bfd_section->filepos;
else if ((hdr->sh_flags & SHF_ALLOC) != 0)
{
- ((*_bfd_error_handler)
- (_("%B: warning: allocated section `%s' not in segment"),
- abfd,
- (hdr->bfd_section == NULL
- ? "*unknown*"
- : hdr->bfd_section->name)));
+ if (hdr->sh_size != 0)
+ ((*_bfd_error_handler)
+ (_("%B: warning: allocated section `%s' not in segment"),
+ abfd,
+ (hdr->bfd_section == NULL
+ ? "*unknown*"
+ : hdr->bfd_section->name)));
if ((abfd->flags & D_PAGED) != 0)
off += vma_page_aligned_bias (hdr->sh_addr, off,
bed->maxpagesize);
--- binutils/ld/ld.texinfo.empty 2006-09-26 12:06:35.000000000 -0700
+++ binutils/ld/ld.texinfo 2006-09-26 15:15:18.000000000 -0700
@@ -3688,7 +3688,7 @@ The linker will not create output sectio
contents. This is for convenience when referring to input sections that
may or may not be present in any of the input files. For example:
@smallexample
-.foo @{ *(.foo) @}
+.foo : @{ *(.foo) @}
@end smallexample
@noindent
will only create a @samp{.foo} section in the output file if there is a
@@ -3698,6 +3698,9 @@ If you use anything other than an input
section command, such as a symbol assignment, then the output section
will always be created, even if there are no matching input sections.
+When a section is discarded, its address (@pxref{Output Section Address})
+will be ignored unless it is provided as a constant.
+
@cindex /DISCARD/
The special output section name @samp{/DISCARD/} may be used to discard
input sections. Any input sections which are assigned to an output
--- binutils/ld/ldlang.c.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/ldlang.c 2006-09-26 15:07:38.000000000 -0700
@@ -3343,6 +3343,7 @@ strip_excluded_output_sections (void)
continue;
exclude = (output_section->rawsize == 0
+ && !os->section_relative_symbol
&& (output_section->flags & SEC_KEEP) == 0
&& !bfd_section_removed_from_list (output_bfd,
output_section));
@@ -3373,6 +3374,11 @@ strip_excluded_output_sections (void)
/* We don't set bfd_section to NULL since bfd_section of the
removed output section statement may still be used. */
os->ignored = TRUE;
+ /* If address of an empty output section is set to a constant,
+ we update "dot" even if it is ignored. */
+ os->ignored_vma
+ = (os->addr_tree == NULL
+ || os->addr_tree->type.node_class != etree_value);
output_section->flags |= SEC_EXCLUDE;
bfd_section_list_remove (output_bfd, output_section);
output_bfd->section_count--;
@@ -4461,7 +4467,7 @@ lang_size_sections_1
}
os->processed_lma = TRUE;
- if (bfd_is_abs_section (os->bfd_section) || os->ignored)
+ if (bfd_is_abs_section (os->bfd_section) || os->ignored_vma)
break;
/* Keep track of normal sections using the default
@@ -4630,11 +4636,19 @@ lang_size_sections_1
case lang_assignment_statement_enum:
{
bfd_vma newdot = dot;
+ etree_type *tree = s->assignment_statement.exp;
- exp_fold_tree (s->assignment_statement.exp,
+ exp_fold_tree (tree,
output_section_statement->bfd_section,
&newdot);
+ /* This symbol is relative to this section. */
+ if ((tree->type.node_class == etree_provided
+ || tree->type.node_class == etree_assign)
+ && (tree->assign.dst [0] != '.'
+ || tree->assign.dst [1] != '\0'))
+ output_section_statement->section_relative_symbol = 1;
+
if (!output_section_statement->ignored)
{
if (output_section_statement == abs_output_section)
@@ -4815,7 +4829,7 @@ lang_do_assignments_1 (lang_statement_un
lang_output_section_statement_type *os;
os = &(s->output_section_statement);
- if (os->bfd_section != NULL && !os->ignored)
+ if (os->bfd_section != NULL && !os->ignored_vma)
{
dot = os->bfd_section->vma;
--- binutils/ld/ldlang.h.empty 2006-09-07 10:16:34.000000000 -0700
+++ binutils/ld/ldlang.h 2006-09-26 15:07:38.000000000 -0700
@@ -153,7 +153,12 @@ typedef struct lang_output_section_state
unsigned int processed_vma : 1;
unsigned int processed_lma : 1;
unsigned int all_input_readonly : 1;
+ /* If this section should be ignored. */
unsigned int ignored : 1;
+ /* If this section VMA should be ignored. */
+ unsigned int ignored_vma : 1;
+ /* If there is a symbol relative to this section. */
+ unsigned int section_relative_symbol : 1;
} lang_output_section_statement_type;
typedef struct
--- binutils/ld/testsuite/ld-scripts/empty-address-1.d.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-1.d 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,8 @@
+#ld: -T empty-address-1.t
+#nm: -n
+#...
+0+0 T _start
+#...
+0+2000000 A __data_end
+0+2000000 D __data_start
+#pass
--- binutils/ld/testsuite/ld-scripts/empty-address-1.s.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-1.s 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,5 @@
+ .text
+ .global _start
+_start:
+ .long __data_start
+ .long __data_end
--- binutils/ld/testsuite/ld-scripts/empty-address-1.t.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-1.t 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,11 @@
+SECTIONS
+{
+ .text 0x0000000: { *(.text) }
+ .data 0x2000000:
+ {
+ __data_start = . ;
+ *(.data)
+ }
+ __data_end = .;
+ /DISCARD/ : { *(.*) }
+}
--- binutils/ld/testsuite/ld-scripts/empty-address-2.s.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-2.s 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,4 @@
+ .text
+ .global _start
+_start:
+ .long __data_end
--- binutils/ld/testsuite/ld-scripts/empty-address-2a.d.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-2a.d 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,8 @@
+#source: empty-address-2.s
+#ld: -Ttext 0x0000000 -Tdata 0x2000000 -T empty-address-2a.t
+#nm: -n
+#...
+0+0 T _start
+#...
+0+2000000 A __data_end
+#pass
--- binutils/ld/testsuite/ld-scripts/empty-address-2a.t.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-2a.t 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,7 @@
+SECTIONS
+{
+ .text : { *(.text) }
+ .data : { *(.data) }
+ __data_end = .;
+ /DISCARD/ : { *(.*) }
+}
--- binutils/ld/testsuite/ld-scripts/empty-address-2b.d.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-2b.d 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,8 @@
+#source: empty-address-2.s
+#ld: -Ttext 0x0000000 -Tdata 0x2000000 -T empty-address-2b.t
+#nm: -n
+#...
+0+0 T _start
+#...
+0+2000000 A __data_end
+#pass
--- binutils/ld/testsuite/ld-scripts/empty-address-2b.t.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-2b.t 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,11 @@
+SECTIONS
+{
+ .text 0x0000000: { *(.text) }
+ .data :
+ {
+ PROVIDE (__data_start = .);
+ *(.data)
+ }
+ __data_end = .;
+ /DISCARD/ : { *(.*) }
+}
--- binutils/ld/testsuite/ld-scripts/empty-address-3.s.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3.s 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,5 @@
+ .text
+ .global _start
+_start:
+ .byte 0,0,0,0,0,0,0,0
+ .byte 0,0,0,0,0,0,0,0
--- binutils/ld/testsuite/ld-scripts/empty-address-3a.d.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3a.d 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,8 @@
+#source: empty-address-3.s
+#ld: -T empty-address-3a.t
+#nm: -n
+#...
+0+0 T _start
+#...
+0+10 A __data_end
+#pass
--- binutils/ld/testsuite/ld-scripts/empty-address-3a.t.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3a.t 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,10 @@
+SECTIONS
+{
+ .text 0x00000000: { *(.text) }
+ .data ALIGN(0x1000) + (. & (0x1000 - 1)):
+ {
+ *(.data)
+ }
+ __data_end = .;
+ /DISCARD/ : { *(.*) }
+}
--- binutils/ld/testsuite/ld-scripts/empty-address-3b.d.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3b.d 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,8 @@
+#source: empty-address-3.s
+#ld: -T empty-address-3b.t
+#nm: -n
+#...
+0+0 T _start
+#...
+0+10 A __data_end
+#pass
--- binutils/ld/testsuite/ld-scripts/empty-address-3b.t.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3b.t 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,11 @@
+SECTIONS
+{
+ .text 0x00000000: { *(.text) }
+ .data ALIGN(0x1000) + (. & (0x1000 - 1)):
+ {
+ PROVIDE (__data_start = .);
+ *(.data)
+ }
+ __data_end = .;
+ /DISCARD/ : { *(.*) }
+}
--- binutils/ld/testsuite/ld-scripts/empty-address-3c.d.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3c.d 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,10 @@
+#source: empty-address-3.s
+#ld: -T empty-address-3c.t
+#nm: -n
+#...
+0+0 T _start
+#...
+0+1010 A __data_end
+#...
+0+1010 D __data_start
+#pass
--- binutils/ld/testsuite/ld-scripts/empty-address-3c.t.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address-3c.t 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,11 @@
+SECTIONS
+{
+ .text 0x00000000: { *(.text) }
+ .data ALIGN(0x1000) + (. & (0x1000 - 1)):
+ {
+ __data_start = .;
+ *(.data)
+ }
+ __data_end = .;
+ /DISCARD/ : { *(.*) }
+}
--- binutils/ld/testsuite/ld-scripts/empty-address.exp.empty 2006-09-26 15:07:38.000000000 -0700
+++ binutils/ld/testsuite/ld-scripts/empty-address.exp 2006-09-26 15:07:38.000000000 -0700
@@ -0,0 +1,25 @@
+# Make sure that "dot" is updated for empty sections if their addresses
+# are set.
+# Copyright 2006
+# Free Software Foundation, Inc.
+#
+# This file 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 2 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.
+
+run_dump_test empty-address-1
+run_dump_test empty-address-2a
+run_dump_test empty-address-2b
+run_dump_test empty-address-3a
+run_dump_test empty-address-3b
+run_dump_test empty-address-3c
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