ld/NEWS

   1 -*- text -*-
   2
   3 * Added --no-omagic to undo the effects of the -N option.
   4
   5 * Support for Texas Instruments TMS320C4x and TMS320C3x series of
   6   DSP's contributed by Michael Hayes and Svein E. Seldal.
   7
   8 * Added --with-lib-path configure switch to specify default value for
   9   LIB_PATH.
  10
  11 * ARM port to QNX operating system added by Graeme Peterson.
  12
  13 * IP2K support added by Denis Chertykov.
  14
  15 Changes in 2.13:
  16
  17 * Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400
  18   and FR500 included.
  19
  20 Changes in version 2.13:
  21
  22 * DEC VAX ELF support, by Matt Thomas.
  23
  24 Changes in version 2.12:
  25
  26 * Support for Don Knuth's MMIX, by Hans-Peter Nilsson.
  27
  28 * Support for the OpenRISC 32-bit embedded processor by OpenCores.
  29
  30 * Support for -z nocopyreloc in the x86 ELF linker, which disables
  31   production of copy relocs.  Warning: using this option may result in
  32   non-sharable applications.
  33
  34 * Support for -z combreloc in the ELF linker, which puts dynamic
  35   relocations against the same symbol together, so that dynamic linker
  36   can use an one-entry symbol lookup cache.
  37
  38 * Support for ELF SHF_MERGE section merging, by Jakub Jelinek.
  39
  40 Changes in version 2.11:
  41
  42 * Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs.
  43
  44 * Support added for eliminating duplicate DWARF2 debug information by
  45   having the compiler generate the information in sections called
  46   .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents.  The
  47   linker then merges these sections together into the normal .debug_info
  48   section.
  49
  50 * The native ELF linker now searches the directories in DT_RUNPATH or
  51   DT_RPATH of a shared library for shared libraries needed by it.
  52
  53 * TI C54x support, by Timothy Wall.
  54
  55 * Added command line switch --section-start to set the start address of any
  56   specified section.
  57
  58 * Added ability to emit full relocation information in linked executables,
  59   enabled by --emit-relocs.  Some post-linkage optimization tools need
  60   this information in order to be able to correctly identify and perform
  61   symbol relative addressing in the event of changes in section contents
  62   (instructions being added or deleted, extending data sections, etc.)
  63
  64 * Support for i860, by Jason Eckhardt (preliminary, alpha quality).
  65
  66 * Support for CRIS (Axis Communications ETRAX series).
  67
  68 * Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff.
  69
  70 Changes in version 2.10:
  71
  72 * Added AT> to the linker script language to allow load-time allocation of
  73   sections into regions.
  74
  75 * Added garbage collection of unused sections, enabled by --gc-sections.
  76   It does require a bit of backend support; currently implemented are
  77   arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf,
  78   mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf.
  79   Others will ignore the option.
  80
  81 * Added SORT to the linker script language to permit sorting sections by file
  82   name or section name.
  83
  84 * Added EXTERN to the linker script language as an equivalent to the -u
  85   command-line option.
  86
  87 * Added ASSERT to the linker script language.
  88
  89 * Added EXCLUDE_FILE to the linker script language for further control over
  90   wildcard file names.
  91
  92 * Added -O option to optimize linker output (as of this writing, this only
  93   affects ELF shared library generation).
  94
  95 * The -e option now accepts a number as well as a symbol name.
  96
  97 * Added --no-undefined option to disallow undefined symbols when creating a
  98   shared library.
  99
 100 * The linker now issues a warning, not an error, for an undefined symbol when
 101   using -Bsymbolic; use the new --no-undefined option to get the old
 102   behaviour.
 103
 104 * Added --demangle and --no-demangle options.
 105
 106 Changes in version 2.9:
 107
 108 * Added SQUAD to the linker script language.
 109
 110 * New option --no-warn-mismatch.
 111
 112 * The MEMORY command now parses the attributes to determine where sections that
 113   are not placed in a specific memory region are placed.
 114
 115 Changes in version 2.8:
 116
 117 * Linker scripts may now contain shell wildcard characters for file and section
 118   names.
 119
 120 * The linker now supports symbol versions in ELF.
 121
 122 * The NOCROSSREFS command was added to the linker script language.
 123
 124 * The LOADADDR expression was added to the linker script language.
 125
 126 * MAX and MIN functions were added to the linker script language.
 127
 128 * The OVERLAY construct was added to the linker script language.
 129
 130 * New option --warn-section-align to warn when the address of an output section
 131   changes due to alignment of an input section.
 132
 133 * New options --filter/-F and --auxiliary/-f.
 134
 135 Changes in version 2.7:
 136
 137 * New option --cref to print out a cross reference table.
 138
 139 * New option --wrap SYMBOL.
 140
 141 * New option --no-whole-archive, to turn off the effect of --whole-archive.
 142
 143 * Input sections assigned to the output section /DISCARD/ in the linker script
 144   are not included in the output file.
 145
 146 * The SunOS and ELF linkers now merge stabs debugging information which uses
 147   the N_BINCL and N_EINCL stab types.  This reduces the amount of debugging
 148   information generated.
 149
 150 Changes in version 2.6:
 151
 152 * When an ELF section name is representable as a C identifier (this is not true
 153 of most ELF section names), the linker will automatically define symbols
 154 __start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the
 155 beginning and the end of the section.  This is used by glibc.
 156
 157 * When an ELF section named .gnu.warning is encountered in an input file, the
 158 contents of the section are displayed as an error message, and the section is
 159 not copied into the output file.  This is used by glibc.
 160
 161 * When an ELF section named .gnu.warning.SYMBOL is encountered in an input
 162 file, and the symbol SYMBOL is referenced by some object file, the contents of
 163 the section are displayed as an error message.  The section is not copied into
 164 the output file, unless doing a relocateable or shared link.  This is used by
 165 glibc.
 166
 167 * New options -split-by-reloc and -split-by-file.
 168
 169 * The linker now supports linking PIC compiled code on SPARC SunOS.  It can
 170 also create SPARC SunOS shared libraries, and, like the native SunOS linker,
 171 will do so whenever there is an undefined symbol in the link and neither the -e
 172 nor the -r option was used.
 173
 174 * The -rpath option may be used on SunOS to set the list of directories to be
 175 searched at run time.  This overrides the default of building the list from the
 176 -L options.
 177
 178 * The COFF linker now combines debugging information for structs, unions, and
 179 enums, so that even if the same type is defined in multiple input files it will
 180 only be defined once in the output file.  The --traditional-format switch will
 181 prevent this optimization.
 182
 183 Changes in version 2.5:
 184
 185 * The linker now supports linking against SunOS shared libraries.  It still can
 186 not link SunOS PIC (Position Independent Code) files, so it can not be used to
 187 generate shared libaries.
 188
 189 * The linker now supports linking against ELF shared libraries for the i386
 190 (UnixWare) and SPARC (Solaris).  It can also link ELF PIC files, and can be
 191 used to generate shared libraries.  Shared library generation is not well
 192 tested; please report any problems encountered.  The linker is now enabled for
 193 Solaris again.
 194
 195 * Eric Youngdale has contributed Linux support code, including linking against
 196 Linux a.out shared libraries.  The linker produces Linux QMAGIC binaries.
 197
 198 * The ELF backend has been converted to the new linker code.  To use the new
 199 ELF linker, each particular target requires a relocation function.  So far,
 200 this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix
 201 5), and HPPA ELF targets.
 202
 203 * The -( (--start-group) and -) (--end-group) options have been added to
 204 support searching a group of archives as though they were a single archive.
 205 This can also be used in a linker script, as GROUP ( files ).
 206
 207 * When a file is named on the command line, and the linker does not recognize
 208 it as an object file, the linker will now treat the file as a linker script
 209 file.  A linker script named in this way augments, but does not replace, the
 210 default linker script.
 211
 212 * The -warn-once option was added.  It causes the linker to only warn once per
 213 undefined symbol, rather than once per reference.
 214
 215 * The COFF backend has been converted to the new linker code.  As with ELF, to
 216 use the new linker, each particular target requires a relocation function.  So
 217 far, this function has been written for the i386, m68k, a29k and SH targets.
 218
 219 * The -V flag was made a synonym for -v, for SVR4 compatibility.  The old -V
 220 behaviour is available via --verbose.
 221
 222 Changes in version 2.4:
 223
 224 * New linker code, by Steve Chamberlain and Ian Taylor.  For a.out and ecoff
 225   formats (so far), this should result in considerable savings in time
 226   and memory used while linking; slightly poorer performance than
 227   before for formats not converted yet.
 228
 229 * Command-line parsing is no longer done with flex.  This means
 230   oddball characters in filenames won't get treated as argument
 231   separators.
 232
 233 * HP-PA ELF support, by Jeff Law.  (No SOM support yet.)
 234
 235 * Mach i386 support, by David Mackenzie.
 236
 237 * Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared
 238   libraries are not yet supported).
 239
 240 * COFF shared libraries (as on SCO) should work as well.
 241
 242 * The linker is disabled for Solaris.  (Actually, it was in 2.3 also, I just
 243   forgot to note it.)  Some of their C library routines don't work when
 244   statically linked, and the GNU linker doesn't support dynamic linking yet.
 245
 246 Changes in version 2.3:
 247
 248 * Weak symbols are now supported.
 249
 250 * ELF support has been added.  The linker has been bootstrapped on
 251   UnixWare and Solaris.
 252
 253 * Alpha OSF/1 support has been added (non dynamic linking only).
 254
 255 Changes in version 2.2:
 256
 257 * The `bfd' library has been updated to reduce a.out-format string
 258   table size.  The effect of this is that files linked from many input
 259   files with duplicate symbols (`-g' debugging records, or identical
 260   static symbols) should be much smaller.
 261
 262 Changes in version 2.1:
 263
 264 * The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented.
 265
 266 * There is now support for writing ECOFF files, so ld and the
 267   other utilities should work on Risc/Ultrix and Irix.
 268
 269 \f
 270 Local variables:
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 272 End: