ld/NEWS

   1 -*- text -*-
   2
   3 Changes in version 2.10:
   4
   5 * Added garbage collection of unused sections, enabled by --gc-sections.
   6   It does require a bit of backend support; currently implemented are
   7   ppc-elf, mips-elf, and mn10300-elf.  Others will ignore the option.
   8
   9 * Added SORT to the linker script language to permit sorting sections by file
  10   name or section name.
  11
  12 * Added EXTERN to the linker script language as an equivalent to the -u
  13   command-line option.
  14
  15 * Added ASSERT to the linker script language.
  16
  17 * Added EXCLUDE_FILE to the linker script language for further control over
  18   wildcard file names.
  19
  20 * Added -O option to optimize linker output (as of this writing, this only
  21 affects ELF shared library generation).
  22
  23 * The -e option now accepts a number as well as a symbol name.
  24
  25 * Added --no-undefined option to disallow undefined symbols when creating a
  26   shared library.
  27
  28 * The linker now issues a warning, not an error, for an undefined symbol when
  29   using -Bsymbolic; use the new --no-undefined option to get the old
  30   behaviour.
  31
  32 * Added --demangle and --no-demangle options.
  33
  34 Changes in version 2.9:
  35
  36 * Added SQUAD to the linker script language.
  37
  38 * New option --no-warn-mismatch.
  39
  40 * The MEMORY command now parses the attributes to determine where sections that
  41   are not placed in a specific memory region are placed.
  42
  43 Changes in version 2.8:
  44
  45 * Linker scripts may now contain shell wildcard characters for file and section
  46   names.
  47
  48 * The linker now supports symbol versions in ELF.
  49
  50 * The NOCROSSREFS command was added to the linker script language.
  51
  52 * The LOADADDR expression was added to the linker script language.
  53
  54 * MAX and MIN functions were added to the linker script language.
  55
  56 * The OVERLAY construct was added to the linker script language.
  57
  58 * New option --warn-section-align to warn when the address of an output section
  59   changes due to alignment of an input section.
  60
  61 * New options --filter/-F and --auxiliary/-f.
  62
  63 Changes in version 2.7:
  64
  65 * New option --cref to print out a cross reference table.
  66
  67 * New option --wrap SYMBOL.
  68
  69 * New option --no-whole-archive, to turn off the effect of --whole-archive.
  70
  71 * Input sections assigned to the output section /DISCARD/ in the linker script
  72   are not included in the output file.
  73
  74 * The SunOS and ELF linkers now merge stabs debugging information which uses
  75   the N_BINCL and N_EINCL stab types.  This reduces the amount of debugging
  76   information generated.
  77
  78 Changes in version 2.6:
  79
  80 * When an ELF section name is representable as a C identifier (this is not true
  81 of most ELF section names), the linker will automatically define symbols
  82 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
  83 beginning and the end of the section.  This is used by glibc.
  84
  85 * When an ELF section named .gnu.warning is encountered in an input file, the
  86 contents of the section are displayed as an error message, and the section is
  87 not copied into the output file.  This is used by glibc.
  88
  89 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
  90 file, and the symbol SYMBOL is referenced by some object file, the contents of
  91 the section are displayed as an error message.  The section is not copied into
  92 the output file, unless doing a relocateable or shared link.  This is used by
  93 glibc.
  94
  95 * New options -split-by-reloc and -split-by-file.
  96
  97 * The linker now supports linking PIC compiled code on SPARC SunOS.  It can
  98 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
  99 will do so whenever there is an undefined symbol in the link and neither the -e
 100 nor the -r option was used.
 101
 102 * The -rpath option may be used on SunOS to set the list of directories to be
 103 searched at run time.  This overrides the default of building the list from the
 104 -L options.
 105
 106 * The COFF linker now combines debugging information for structs, unions, and
 107 enums, so that even if the same type is defined in multiple input files it will
 108 only be defined once in the output file.  The --traditional-format switch will
 109 prevent this optimization.
 110
 111 Changes in version 2.5:
 112
 113 * The linker now supports linking against SunOS shared libraries.  It still can
 114 not link SunOS PIC (Position Independent Code) files, so it can not be used to
 115 generate shared libaries.
 116
 117 * The linker now supports linking against ELF shared libraries for the i386
 118 (UnixWare) and SPARC (Solaris).  It can also link ELF PIC files, and can be
 119 used to generate shared libraries.  Shared library generation is not well
 120 tested; please report any problems encountered.  The linker is now enabled for
 121 Solaris again.
 122
 123 * Eric Youngdale has contributed Linux support code, including linking against
 124 Linux a.out shared libraries.  The linker produces Linux QMAGIC binaries.
 125
 126 * The ELF backend has been converted to the new linker code.  To use the new
 127 ELF linker, each particular target requires a relocation function.  So far,
 128 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
 129 5), and HPPA ELF targets.
 130
 131 * The -( (--start-group) and -) (--end-group) options have been added to
 132 support searching a group of archives as though they were a single archive.
 133 This can also be used in a linker script, as GROUP ( files ).
 134
 135 * When a file is named on the command line, and the linker does not recognize
 136 it as an object file, the linker will now treat the file as a linker script
 137 file.  A linker script named in this way augments, but does not replace, the
 138 default linker script.
 139
 140 * The -warn-once option was added.  It causes the linker to only warn once per
 141 undefined symbol, rather than once per reference.
 142
 143 * The COFF backend has been converted to the new linker code.  As with ELF, to
 144 use the new linker, each particular target requires a relocation function.  So
 145 far, this function has been written for the i386, m68k, a29k and SH targets.
 146
 147 * The -V flag was made a synonym for -v, for SVR4 compatibility.  The old -V
 148 behaviour is available via --verbose.
 149
 150 Changes in version 2.4:
 151
 152 * New linker code, by Steve Chamberlain and Ian Taylor.  For a.out and ecoff
 153   formats (so far), this should result in considerable savings in time
 154   and memory used while linking; slightly poorer performance than
 155   before for formats not converted yet.
 156
 157 * Command-line parsing is no longer done with flex.  This means
 158   oddball characters in filenames won't get treated as argument
 159   separators.
 160
 161 * HP-PA ELF support, by Jeff Law.  (No SOM support yet.)
 162
 163 * Mach i386 support, by David Mackenzie.
 164
 165 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
 166   libraries are not yet supported).
 167
 168 * COFF shared libraries (as on SCO) should work as well.
 169
 170 * The linker is disabled for Solaris.  (Actually, it was in 2.3 also, I just
 171   forgot to note it.)  Some of their C library routines don't work when
 172   statically linked, and the GNU linker doesn't support dynamic linking yet.
 173
 174 Changes in version 2.3:
 175
 176 * Weak symbols are now supported.
 177
 178 * ELF support has been added.  The linker has been bootstrapped on
 179   UnixWare and Solaris.
 180
 181 * Alpha OSF/1 support has been added (non dynamic linking only).
 182
 183 Changes in version 2.2:
 184
 185 * The `bfd' library has been updated to reduce a.out-format string
 186   table size.  The effect of this is that files linked from many input
 187   files with duplicate symbols (`-g' debugging records, or identical
 188   static symbols) should be much smaller.
 189
 190 Changes in version 2.1:
 191
 192 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
 193
 194 * There is now support for writing ECOFF files, so ld and the
 195   other utilities should work on Risc/Ultrix and Irix.
 196
 197 \f
 198 Local variables:
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 200 End: