[binutils-gdb] elf: Set rel_from_abs to 1 for __ehdr_start

[H.J. Lu]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=cbd5b99cce073273f668b154d4514e8e7e7ccc51

commit cbd5b99cce073273f668b154d4514e8e7e7ccc51
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Nov 13 15:44:35 2020 -0800

    elf: Set rel_from_abs to 1 for __ehdr_start
    
    bfdlink.h has
    
      /* Symbol will be converted from absolute to section-relative.  Set for
         symbols defined by a script from "dot" (also SEGMENT_START or ORIGIN)
         outside of an output section statement.  */
      unsigned int rel_from_abs : 1;
    
    linker.c has
    
    .{* Return TRUE if the symbol described by a linker hash entry H
    .   is going to be absolute.  Linker-script defined symbols can be
    .   converted from absolute to section-relative ones late in the
    .   link.  Use this macro to correctly determine whether the symbol
    .   will actually end up absolute in output.  *}
    .#define bfd_is_abs_symbol(H) \
    .  (((H)->type == bfd_link_hash_defined \
    .    || (H)->type == bfd_link_hash_defweak) \
    .   && bfd_is_abs_section ((H)->u.def.section) \
    .   && !(H)->rel_from_abs)
    .
    
    Set rel_from_abs to 1 for __ehdr_start which will be converted from
    absolute to section-relative in assign_file_positions_for_load_sections.
    
            PR ld/26869
            * ldelf.c (ldelf_before_allocation): Set rel_from_abs to 1 for
            __ehdr_start.
            * testsuite/ld-i386/i386.exp: Run pr26869.
            * testsuite/ld-i386/pr26869.d: New file.
            * testsuite/ld-i386/pr26869.s: Likewise.

Diff:
---
 ld/ChangeLog                   |  9 +++++++++
 ld/ldelf.c                     |  2 ++
 ld/testsuite/ld-i386/i386.exp  |  1 +
 ld/testsuite/ld-i386/pr26869.d | 14 ++++++++++++++
 ld/testsuite/ld-i386/pr26869.s |  3 +++
 5 files changed, 29 insertions(+)

diff --git a/ld/ChangeLog b/ld/ChangeLog
index d5d37b1da32..70ea14b4191 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,12 @@
+2020-11-13  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/26869
+	* ldelf.c (ldelf_before_allocation): Set rel_from_abs to 1 for
+	__ehdr_start.
+	* testsuite/ld-i386/i386.exp: Run pr26869.
+	* testsuite/ld-i386/pr26869.d: New file.
+	* testsuite/ld-i386/pr26869.s: Likewise.
+
 2020-11-09  Andreas Schwab  <schwab@linux-m68k.org>
 
 	* Makefile.am (development.exp): Fix regexp.
diff --git a/ld/ldelf.c b/ld/ldelf.c
index c37358f05e5..5cfddef39b3 100644
--- a/ld/ldelf.c
+++ b/ld/ldelf.c
@@ -1590,6 +1590,8 @@ ldelf_before_allocation (char *audit, char *depaudit,
 		      (char *) &ehdr_start->u + sizeof ehdr_start->u.def.next,
 		      sizeof ehdr_start_save_u);
 	      ehdr_start->type = bfd_link_hash_defined;
+	      /* It will be converted to section-relative later.  */
+	      ehdr_start->rel_from_abs = 1;
 	      ehdr_start->u.def.section = bfd_abs_section_ptr;
 	      ehdr_start->u.def.value = 0;
 	    }
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index 9c06f7006b7..0620721559e 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -480,6 +480,7 @@ run_dump_test "property-x86-isa1"
 run_dump_test "property-x86-isa2"
 run_dump_test "property-x86-isa3"
 run_dump_test "property-x86-isa4"
+run_dump_test "pr26869"
 
 if { !([istarget "i?86-*-linux*"]
        || [istarget "i?86-*-gnu*"]
diff --git a/ld/testsuite/ld-i386/pr26869.d b/ld/testsuite/ld-i386/pr26869.d
new file mode 100644
index 00000000000..bfd00a70e9b
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr26869.d
@@ -0,0 +1,14 @@
+#as: --32
+#ld: -shared -melf_i386
+#readelf: -r -s --wide
+
+Relocation section '.rel.dyn' at offset 0x[a-f0-9]+ contains 1 entry:
+ Offset     Info    Type                Sym. Value  Symbol's Name
+0+[a-f0-9]+  00000008 R_386_RELATIVE        
+
+#...
+Symbol table '.symtab' contains [0-9]+ entries:
+   Num:    Value  Size Type    Bind   Vis      Ndx Name
+#...
+ +[a-f0-9]+: 00000000     0 NOTYPE  LOCAL  DEFAULT    1 __ehdr_start
+#pass
diff --git a/ld/testsuite/ld-i386/pr26869.s b/ld/testsuite/ld-i386/pr26869.s
new file mode 100644
index 00000000000..e492b98e869
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr26869.s
@@ -0,0 +1,3 @@
+	.text
+foo:
+	pushl	__ehdr_start@GOT(%ebx)