Fix several mix up between octets and bytes in ELF program headers

[deliverable/binutils-gdb.git] / include / elf / reloc-macros.h

diff --git a/include/elf/reloc-macros.h b/include/elf/reloc-macros.h
index a67419d220ca2ae819e4c02049467dabd38f3b01..7ff6a41a44e494d2140bec12c710dc583463a785 100644 (file)
--- a/include/elf/reloc-macros.h
+++ b/include/elf/reloc-macros.h
@@ -1,11 +1,11 @@
 /* Generic relocation support for BFD.
-   Copyright 1998, 1999, 2000, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1998-2020 Free Software Foundation, Inc.
 
    This file is part of BFD, the Binary File Descriptor library.
 
    This program 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
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
@@ -43,6 +43,34 @@
          R_foo_count
        };
 
+   Note: The value of the symbol defined in the END_RELOC_NUMBERS
+   macro (R_foo_count in the case of the example above) will be
+   set to the value of the whichever *_RELOC macro precedes it plus
+   one.  Therefore if you intend to use the symbol as a sentinel for
+   the highest valid macro value you should make sure that the
+   preceding *_RELOC macro is the highest valid number.  ie a
+   declaration like this:
+
+       START_RELOC_NUMBERS (foo)
+           RELOC_NUMBER (R_foo_NONE,    0)
+           RELOC_NUMBER (R_foo_32,      1)
+           FAKE_RELOC   (R_foo_illegal, 9)
+           FAKE_RELOC   (R_foo_synonym, 0)
+       END_RELOC_NUMBERS (R_foo_count)
+
+   will result in R_foo_count having a value of 1 (R_foo_synonym + 1)
+   rather than 10 or 2 as might be expected.
+
+   Alternatively you can assign a value to END_RELOC_NUMBERS symbol
+   explicitly, like this:
+
+       START_RELOC_NUMBERS (foo)
+           RELOC_NUMBER (R_foo_NONE,    0)
+           RELOC_NUMBER (R_foo_32,      1)
+           FAKE_RELOC   (R_foo_illegal, 9)
+           FAKE_RELOC   (R_foo_synonym, 0)
+       END_RELOC_NUMBERS (R_foo_count = 2)
+
    If RELOC_MACROS_GEN_FUNC *is* defined, then instead the
    following function will be generated: