1-*- text -*- 2 3* Support for the Infineon XC16X has been added by KPIT Cummins Infosystems. 4 5* Modify the Linux linker search order to better match ld.so search order. 6 Look for DT_NEEDED libraries in paths specified by ld.so.conf before 7 searching the default directories, rather than vice versa. 8 Use $prefix/etc/ld.so.conf if it exists, otherwise /etc/ld.so.conf. 9 10* PE-COFF: Forward exports from DLL's can now be specified in .def files 11 passed directly to ld. 12 13* Support for the Z80 processor family has been added. 14 15* Add support for the "@<file>" syntax to the command line, so that extra 16 switches can be read from <file>. 17 18Changes in 2.16: 19 20* Support for the R_ARM_V4BX relocation as defined in the ARM AAELF 21 specification has been added via the --fix-v4bx command-line option. 22 23* New linker script construct AS_NEEDED(), which sets the --as-needed flag 24 for input files listed inside of it. 25 26* A new command-line option, --sysroot, can be used to override the 27 default sysroot location. It only applies to toolchains that were 28 configured using --with-sysroot. 29 30* New linker script functions: ORIGIN() and LENGTH() which return information 31 about a specified memory region. 32 33* Port to MAXQ processor contributed by HCL Tech. 34 35* Added SEGMENT_START to the linker script language to permit the user to 36 override the base address for a segment from the command-line. 37 38* ELF: --warn-shared-textrel option to warn if adding a DT_TEXTREL to a shared 39 object. 40 41* Added SORT_BY_NAME and SORT_BY_ALIGNMENT to the linker script 42 language to permit sorting sections by section name or section 43 maximum alignment. 44 45* Added a new linker command line switch, --sort-section name|alignment, 46 to sort sections by section name or maximum alignment. 47 48* ELF: --add-needed/--no-add-needed options to control if a DT_NEEDED tag 49 should be added when a shared library comes from DT_NEEDED tags. 50 51* Support for the crx-elf target added. 52 53* Support for the sh-symbianelf target added. 54 55* A new linker command line switch has been added which allows the hash table 56 size to be set to a suitable prime value near to its argument. This switch 57 is --hash-size=<NUMBER>. Also if the switch --reduce-memory-overheads is 58 used, and --hash-size has not been used, then the default value will be set 59 to 1021. 60 61* Linker map files are now generated with an O(N) algorithm for finding symbols 62 that are defined in each section. This uses about 40% more memory for 63 symbols than the old O(N^2) algorithm. You can use the new 64 --reduce-memory-overheads option to select the old algorithm; this option 65 might also be used in the future to select similar tradeoffs. 66 67Changes in 2.15: 68 69* ELF: --as-needed/--no-as-needed options to control if a DT_NEEDED tag should 70 be added only when a shared library is referenced. 71 72* PE: --large-address-aware option to indicate executables support virtual 73 addresses greater than 2 gigabytes. 74 75* DWARF 2 support for i386pe added. 76 77* The linker script operator DEFINED() will now yield 1 only for a symbol that 78 is defined before the statement where DEFINED is used. 79 80* The MIPS --embedded-relocs (used to embed relocations into binaries for 81 Embedded-PIC code) is deprecated and will be removed in a future release. 82 83* cr16c support added by NSC. 84 85* m32r Linux (ELF) support added by Renesas. 86 87* Improved linker's handling of unresolved symbols. The switch 88 --unresolved-symbols=<method> has been added to tell the linker when it 89 should report them and the switch --warn-unresolved-symbols has been added to 90 make reports be issued as warning messages rather than errors. 91 92Changes in 2.14: 93 94* Added support for Xtensa architecture. 95 96* Added --with-sysroot configure switch to specify a target system root, for 97 linking against a target filesystem image. 98 99* Added --accept-unknown-linker-format to restore old linker behaviour (pre 100 2.14) of silently accepting and linking in any files in an unknown binary 101 file format. 102 103* Added --no-omagic to undo the effects of the -N option. 104 105* Support for Texas Instruments TMS320C4x and TMS320C3x series of 106 DSP's contributed by Michael Hayes and Svein E. Seldal. 107 108* Added --with-lib-path configure switch to specify default value for 109 LIB_PATH. 110 111* ARM port to QNX operating system added by Graeme Peterson. 112 113* IP2K support added by Denis Chertykov. 114 115Changes in 2.13: 116 117* Support for the Fujitsu FRV architecture added by Red Hat. Models for FR400 118 and FR500 included. 119 120Changes in version 2.13: 121 122* DEC VAX ELF support, by Matt Thomas. 123 124Changes in version 2.12: 125 126* Support for Don Knuth's MMIX, by Hans-Peter Nilsson. 127 128* Support for the OpenRISC 32-bit embedded processor by OpenCores. 129 130* Support for -z nocopyreloc in the x86 ELF linker, which disables 131 production of copy relocs. Warning: using this option may result in 132 non-sharable applications. 133 134* Support for -z combreloc in the ELF linker, which puts dynamic 135 relocations against the same symbol together, so that dynamic linker 136 can use an one-entry symbol lookup cache. 137 138* Support for ELF SHF_MERGE section merging, by Jakub Jelinek. 139 140Changes in version 2.11: 141 142* Support for AMD x86-64 architecture, by Jan Hubicka, SuSE Labs. 143 144* Support added for eliminating duplicate DWARF2 debug information by 145 having the compiler generate the information in sections called 146 .gnu.linkonce.wi.XXXX where XXXX is a checksum for the contents. The 147 linker then merges these sections together into the normal .debug_info 148 section. 149 150* The native ELF linker now searches the directories in DT_RUNPATH or 151 DT_RPATH of a shared library for shared libraries needed by it. 152 153* TI C54x support, by Timothy Wall. 154 155* Added command line switch --section-start to set the start address of any 156 specified section. 157 158* Added ability to emit full relocation information in linked executables, 159 enabled by --emit-relocs. Some post-linkage optimization tools need 160 this information in order to be able to correctly identify and perform 161 symbol relative addressing in the event of changes in section contents 162 (instructions being added or deleted, extending data sections, etc.) 163 164* Support for i860, by Jason Eckhardt (preliminary, alpha quality). 165 166* Support for CRIS (Axis Communications ETRAX series). 167 168* Support for PDP-11 and 2.11BSD a.out format, by Lars Brinkhoff. 169 170Changes in version 2.10: 171 172* Added AT> to the linker script language to allow load-time allocation of 173 sections into regions. 174 175* Added garbage collection of unused sections, enabled by --gc-sections. 176 It does require a bit of backend support; currently implemented are 177 arm-elf, avr-elf, d10v-elf, fr30-elf, i386-elf, m32r-elf, m68k-elf, 178 mcore-elf, mips-elf, mn10300-elf, ppc-elf, sh-elf, sparc-elf, and v850-elf. 179 Others will ignore the option. 180 181* Added SORT to the linker script language to permit sorting sections by file 182 name or section name. 183 184* Added EXTERN to the linker script language as an equivalent to the -u 185 command-line option. 186 187* Added ASSERT to the linker script language. 188 189* Added EXCLUDE_FILE to the linker script language for further control over 190 wildcard file names. 191 192* Added -O option to optimize linker output (as of this writing, this only 193 affects ELF shared library generation). 194 195* The -e option now accepts a number as well as a symbol name. 196 197* Added --no-undefined option to disallow undefined symbols when creating a 198 shared library. 199 200* The linker now issues a warning, not an error, for an undefined symbol when 201 using -Bsymbolic; use the new --no-undefined option to get the old 202 behaviour. 203 204* Added --demangle and --no-demangle options. 205 206Changes in version 2.9: 207 208* Added SQUAD to the linker script language. 209 210* New option --no-warn-mismatch. 211 212* The MEMORY command now parses the attributes to determine where sections that 213 are not placed in a specific memory region are placed. 214 215Changes in version 2.8: 216 217* Linker scripts may now contain shell wildcard characters for file and section 218 names. 219 220* The linker now supports symbol versions in ELF. 221 222* The NOCROSSREFS command was added to the linker script language. 223 224* The LOADADDR expression was added to the linker script language. 225 226* MAX and MIN functions were added to the linker script language. 227 228* The OVERLAY construct was added to the linker script language. 229 230* New option --warn-section-align to warn when the address of an output section 231 changes due to alignment of an input section. 232 233* New options --filter/-F and --auxiliary/-f. 234 235Changes in version 2.7: 236 237* New option --cref to print out a cross reference table. 238 239* New option --wrap SYMBOL. 240 241* New option --no-whole-archive, to turn off the effect of --whole-archive. 242 243* Input sections assigned to the output section /DISCARD/ in the linker script 244 are not included in the output file. 245 246* The SunOS and ELF linkers now merge stabs debugging information which uses 247 the N_BINCL and N_EINCL stab types. This reduces the amount of debugging 248 information generated. 249 250Changes in version 2.6: 251 252* When an ELF section name is representable as a C identifier (this is not true 253of most ELF section names), the linker will automatically define symbols 254__start_SECNAME and __stop_SECNAME, where SECNAME is the section name, at the 255beginning and the end of the section. This is used by glibc. 256 257* When an ELF section named .gnu.warning is encountered in an input file, the 258contents of the section are displayed as an error message, and the section is 259not copied into the output file. This is used by glibc. 260 261* When an ELF section named .gnu.warning.SYMBOL is encountered in an input 262file, and the symbol SYMBOL is referenced by some object file, the contents of 263the section are displayed as an error message. The section is not copied into 264the output file, unless doing a relocatable or shared link. This is used by 265glibc. 266 267* New options -split-by-reloc and -split-by-file. 268 269* The linker now supports linking PIC compiled code on SPARC SunOS. It can 270also create SPARC SunOS shared libraries, and, like the native SunOS linker, 271will do so whenever there is an undefined symbol in the link and neither the -e 272nor the -r option was used. 273 274* The -rpath option may be used on SunOS to set the list of directories to be 275searched at run time. This overrides the default of building the list from the 276-L options. 277 278* The COFF linker now combines debugging information for structs, unions, and 279enums, so that even if the same type is defined in multiple input files it will 280only be defined once in the output file. The --traditional-format switch will 281prevent this optimization. 282 283Changes in version 2.5: 284 285* The linker now supports linking against SunOS shared libraries. It still can 286not link SunOS PIC (Position Independent Code) files, so it can not be used to 287generate shared libraries. 288 289* The linker now supports linking against ELF shared libraries for the i386 290(UnixWare) and SPARC (Solaris). It can also link ELF PIC files, and can be 291used to generate shared libraries. Shared library generation is not well 292tested; please report any problems encountered. The linker is now enabled for 293Solaris again. 294 295* Eric Youngdale has contributed Linux support code, including linking against 296Linux a.out shared libraries. The linker produces Linux QMAGIC binaries. 297 298* The ELF backend has been converted to the new linker code. To use the new 299ELF linker, each particular target requires a relocation function. So far, 300this function has been written for i386 (UnixWare), SPARC (Solaris) MIPS (Irix 3015), and HPPA ELF targets. 302 303* The -( (--start-group) and -) (--end-group) options have been added to 304support searching a group of archives as though they were a single archive. 305This can also be used in a linker script, as GROUP ( files ). 306 307* When a file is named on the command line, and the linker does not recognize 308it as an object file, the linker will now treat the file as a linker script 309file. A linker script named in this way augments, but does not replace, the 310default linker script. 311 312* The -warn-once option was added. It causes the linker to only warn once per 313undefined symbol, rather than once per reference. 314 315* The COFF backend has been converted to the new linker code. As with ELF, to 316use the new linker, each particular target requires a relocation function. So 317far, this function has been written for the i386, m68k, a29k and SH targets. 318 319* The -V flag was made a synonym for -v, for SVR4 compatibility. The old -V 320behaviour is available via --verbose. 321 322Changes in version 2.4: 323 324* New linker code, by Steve Chamberlain and Ian Taylor. For a.out and ecoff 325 formats (so far), this should result in considerable savings in time 326 and memory used while linking; slightly poorer performance than 327 before for formats not converted yet. 328 329* Command-line parsing is no longer done with flex. This means 330 oddball characters in filenames won't get treated as argument 331 separators. 332 333* HP-PA ELF support, by Jeff Law. (No SOM support yet.) 334 335* Mach i386 support, by David Mackenzie. 336 337* Irix 4 shared libraries are now supported (Irix 5 uses ELF, and ELF shared 338 libraries are not yet supported). 339 340* COFF shared libraries (as on SCO) should work as well. 341 342* The linker is disabled for Solaris. (Actually, it was in 2.3 also, I just 343 forgot to note it.) Some of their C library routines don't work when 344 statically linked, and the GNU linker doesn't support dynamic linking yet. 345 346Changes in version 2.3: 347 348* Weak symbols are now supported. 349 350* ELF support has been added. The linker has been bootstrapped on 351 UnixWare and Solaris. 352 353* Alpha OSF/1 support has been added (non dynamic linking only). 354 355Changes in version 2.2: 356 357* The `bfd' library has been updated to reduce a.out-format string 358 table size. The effect of this is that files linked from many input 359 files with duplicate symbols (`-g' debugging records, or identical 360 static symbols) should be much smaller. 361 362Changes in version 2.1: 363 364* The ld -ySYMBOL flag (to trace references to SYMBOL) is now implemented. 365 366* There is now support for writing ECOFF files, so ld and the 367 other utilities should work on Risc/Ultrix and Irix. 368 369 370Local variables: 371fill-column: 79 372End: 373