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-rw-r--r--csu/abi-note.S72
1 files changed, 37 insertions, 35 deletions
diff --git a/csu/abi-note.S b/csu/abi-note.S
index d2051e5b3b..a5014ab5cc 100644
--- a/csu/abi-note.S
+++ b/csu/abi-note.S
@@ -26,44 +26,46 @@
write to the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
-#include <sysdep.h>
+/* Define an ELF note identifying the operating-system ABI that the
+ executable was created for. The ELF note information identifies a
+ particular OS or coordinated development effort within which the
+ ELF header's e_machine value plus (for dynamically linked programs)
+ the PT_INTERP dynamic linker name and DT_NEEDED shared library
+ names fully identify the runtime environment required by an
+ executable.
-/* The basic layout of note sections is specified by the ELF format. */
+ The general format of ELF notes is as follows.
+ Offsets and lengths are bytes or (parenthetical references) to the
+ values in other fields.
-#define ELF_NOTE_BEGIN(sectname, sectflags, type, name) \
- .section sectname, sectflags; \
- .align 4; /* Notes are 4-byte aligned. */ \
- .long 1f - 0f; /* 32-bit word: length of name field */ \
- .long 3f - 2f; /* 32-bit word: length of desc field */ \
- .long (type); /* 32-bit word: vendor-defined type field */ \
-0: .asciz name; /* null-terminated string, any length: name */\
-1: .align 4; /* Name data padded to 4-byte alignment. */ \
-2: /* Here follows the "note descriptor" data, whose format \
- is not specified by ELF. The vendor name and type field \
- indicate what sort of data is found here. */
+offset length contents
+0 4 length of name
+4 4 length of data
+8 4 note type
+12 (0) vendor name
+ - null-terminated ASCII string, padded to 4-byte alignment
+12+(0) (4) note data,
-#define ELF_NOTE_END \
-3: .align 4 /* Pad to 4-byte align the next note. */
-
-
-/* The linker (GNU ld 2.8 and later) recognize an allocated section whose
- name begins with `.note' and creates a PT_NOTE program header entry
- pointing at it.
-
- Such a program header is the canonical way (at least in the free OS
- community) to identify the OS environment ABI that the executable was
- created for. The ELF note information identifies a particular OS or
- coordinated development effort within which the ELF header's e_machine
- value plus (for dynamically linked programs) the PT_INTERP dynamic
- linker name and DT_NEEDED shared library names fully identify the
- runtime environment required by an executable.
-
- The GNU project and cooperating development efforts (including the Linux
- community) use a vendor name string of "GNU", and a note type field with
- value 1 for a note descriptor that indicates ABI requirements. */
+ The GNU project and cooperating development efforts (including the
+ Linux community) use note type 1 and a vendor name string of "GNU"
+ for a note descriptor that indicates ABI requirements. The note data
+ is four 32-bit words. The first of these is an operating system
+ number (0=Hurd, 1=Linux, 2=Solaris, ...) and the remaining three
+ identify the earliest release of that OS that supports this ABI.
+ See abi-tags (top level) for details. */
#include <abi-tag.h> /* OS-specific ABI tag value */
+
+/* The linker (GNU ld 2.8 and later) recognizes an allocated section whose
+ name begins with `.note' and creates a PT_NOTE program header entry
+ pointing at it. */
-ELF_NOTE_BEGIN(".note.ABI-tag", "a", 1, "GNU")
- .long ABI_TAG
-ELF_NOTE_END
+ .section ".note.ABI-tag", "a"
+ .align 4
+ .long 1f - 0f /* name length */
+ .long 3f - 2f /* data length */
+ .long 1 /* note type */
+0: .asciz "GNU" /* vendor name */
+1: .align 4
+2: .long ABI_TAG /* note data: the ABI tag */
+3: .align 4 /* pad out section */