| 1 | What has changed since GDB-3.5? |
| 2 | (Organized release by release) |
| 3 | |
| 4 | *** Changes in GDB-4.9: |
| 5 | |
| 6 | * Testsuite |
| 7 | |
| 8 | This is the first GDB release which is accompanied by a matching testsuite. |
| 9 | The testsuite requires installation of dejagnu, which should be available |
| 10 | via ftp from most sites that carry GNU software. |
| 11 | |
| 12 | * C++ demangling |
| 13 | |
| 14 | 'Cfront' style demangling has had its name changed to 'ARM' style, to |
| 15 | emphasize that it was written from the specifications in the C++ Annotated |
| 16 | Reference Manual, not necessarily to be compatible with AT&T cfront. Despite |
| 17 | disclaimers, it still generated too much confusion with users attempting to |
| 18 | use gdb with AT&T cfront. |
| 19 | |
| 20 | * Simulators |
| 21 | |
| 22 | GDB now uses a standard remote interface to a simulator library. |
| 23 | So far, the library contains simulators for the Zilog Z8001/2, the |
| 24 | Hitachi H8/300, H8/500 and Super-H. |
| 25 | |
| 26 | * New targets supported |
| 27 | |
| 28 | H8/300 simulator h8300-hitachi-hms or h8300hms |
| 29 | H8/500 simulator h8500-hitachi-hms or h8500hms |
| 30 | SH simulator sh-hitachi-hms or sh |
| 31 | Z8000 simulator z8k-zilog-none or z8ksim |
| 32 | IDT MIPS board over serial line mips-idt-ecoff |
| 33 | |
| 34 | Cross-debugging to GO32 targets is supported. It requires a custom |
| 35 | version of the i386-stub.c module which is integrated with the |
| 36 | GO32 memory extender. |
| 37 | |
| 38 | * New remote protocols |
| 39 | |
| 40 | MIPS remote debugging protocol. |
| 41 | |
| 42 | * New source languages supported |
| 43 | |
| 44 | This version includes preliminary support for Chill, a Pascal like language |
| 45 | used by telecommunications companies. Chill support is also being integrated |
| 46 | into the GNU compiler, but we don't know when it will be publically available. |
| 47 | |
| 48 | |
| 49 | *** Changes in GDB-4.8: |
| 50 | |
| 51 | * HP Precision Architecture supported |
| 52 | |
| 53 | GDB now supports HP PA-RISC machines running HPUX. A preliminary |
| 54 | version of this support was available as a set of patches from the |
| 55 | University of Utah. GDB does not support debugging of programs |
| 56 | compiled with the HP compiler, because HP will not document their file |
| 57 | format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS |
| 58 | (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z). |
| 59 | |
| 60 | Many problems in the preliminary version have been fixed. |
| 61 | |
| 62 | * Faster and better demangling |
| 63 | |
| 64 | We have improved template demangling and fixed numerous bugs in the GNU style |
| 65 | demangler. It can now handle type modifiers such as `static' or `const'. Wide |
| 66 | character types (wchar_t) are now supported. Demangling of each symbol is now |
| 67 | only done once, and is cached when the symbol table for a file is read in. |
| 68 | This results in a small increase in memory usage for C programs, a moderate |
| 69 | increase in memory usage for C++ programs, and a fantastic speedup in |
| 70 | symbol lookups. |
| 71 | |
| 72 | `Cfront' style demangling still doesn't work with AT&T cfront. It was written |
| 73 | from the specifications in the Annotated Reference Manual, which AT&T's |
| 74 | compiler does not actually implement. |
| 75 | |
| 76 | * G++ multiple inheritance compiler problem |
| 77 | |
| 78 | In the 2.3.2 release of gcc/g++, how the compiler resolves multiple |
| 79 | inheritance lattices was reworked to properly discover ambiguities. We |
| 80 | recently found an example which causes this new algorithm to fail in a |
| 81 | very subtle way, producing bad debug information for those classes. |
| 82 | The file 'gcc.patch' (in this directory) can be applied to gcc to |
| 83 | circumvent the problem. A future GCC release will contain a complete |
| 84 | fix. |
| 85 | |
| 86 | The previous G++ debug info problem (mentioned below for the gdb-4.7 |
| 87 | release) is fixed in gcc version 2.3.2. |
| 88 | |
| 89 | * Improved configure script |
| 90 | |
| 91 | The `configure' script will now attempt to guess your system type if |
| 92 | you don't supply a host system type. The old scheme of supplying a |
| 93 | host system triplet is preferable over using this. All the magic is |
| 94 | done in the new `config.guess' script. Examine it for details. |
| 95 | |
| 96 | We have also brought our configure script much more in line with the FSF's |
| 97 | version. It now supports the --with-xxx options. In particular, |
| 98 | `--with-minimal-bfd' can be used to make the GDB binary image smaller. |
| 99 | The resulting GDB will not be able to read arbitrary object file formats -- |
| 100 | only the format ``expected'' to be used on the configured target system. |
| 101 | We hope to make this the default in a future release. |
| 102 | |
| 103 | * Documentation improvements |
| 104 | |
| 105 | There's new internal documentation on how to modify GDB, and how to |
| 106 | produce clean changes to the code. We implore people to read it |
| 107 | before submitting changes. |
| 108 | |
| 109 | The GDB manual uses new, sexy Texinfo conditionals, rather than arcane |
| 110 | M4 macros. The new texinfo.tex is provided in this release. Pre-built |
| 111 | `info' files are also provided. To build `info' files from scratch, |
| 112 | you will need the latest `makeinfo' release, which will be available in |
| 113 | a future texinfo-X.Y release. |
| 114 | |
| 115 | *NOTE* The new texinfo.tex can cause old versions of TeX to hang. |
| 116 | We're not sure exactly which versions have this problem, but it has |
| 117 | been seen in 3.0. We highly recommend upgrading to TeX version 3.141 |
| 118 | or better. If that isn't possible, there is a patch in |
| 119 | `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work |
| 120 | around this problem. |
| 121 | |
| 122 | * New features |
| 123 | |
| 124 | GDB now supports array constants that can be used in expressions typed in by |
| 125 | the user. The syntax is `{element, element, ...}'. Ie: you can now type |
| 126 | `print {1, 2, 3}', and it will build up an array in memory malloc'd in |
| 127 | the target program. |
| 128 | |
| 129 | The new directory `gdb/sparclite' contains a program that demonstrates |
| 130 | how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor. |
| 131 | |
| 132 | * New native hosts supported |
| 133 | |
| 134 | HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux |
| 135 | 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4 |
| 136 | |
| 137 | * New targets supported |
| 138 | |
| 139 | AMD 29k family via UDI a29k-amd-udi or udi29k |
| 140 | |
| 141 | * New file formats supported |
| 142 | |
| 143 | BFD now supports reading HP/PA-RISC executables (SOM file format?), |
| 144 | HPUX core files, and SCO 3.2v2 core files. |
| 145 | |
| 146 | * Major bug fixes |
| 147 | |
| 148 | Attaching to processes now works again; thanks for the many bug reports. |
| 149 | |
| 150 | We have also stomped on a bunch of core dumps caused by |
| 151 | printf_filtered("%s") problems. |
| 152 | |
| 153 | We eliminated a copyright problem on the rpc and ptrace header files |
| 154 | for VxWorks, which was discovered at the last minute during the 4.7 |
| 155 | release. You should now be able to build a VxWorks GDB. |
| 156 | |
| 157 | You can now interrupt gdb while an attached process is running. This |
| 158 | will cause the attached process to stop, and give control back to GDB. |
| 159 | |
| 160 | We fixed problems caused by using too many file descriptors |
| 161 | for reading symbols from object files and libraries. This was |
| 162 | especially a problem for programs that used many (~100) shared |
| 163 | libraries. |
| 164 | |
| 165 | The `step' command now only enters a subroutine if there is line number |
| 166 | information for the subroutine. Otherwise it acts like the `next' |
| 167 | command. Previously, `step' would enter subroutines if there was |
| 168 | any debugging information about the routine. This avoids problems |
| 169 | when using `cc -g1' on MIPS machines. |
| 170 | |
| 171 | * Internal improvements |
| 172 | |
| 173 | GDB's internal interfaces have been improved to make it easier to support |
| 174 | debugging of multiple languages in the future. |
| 175 | |
| 176 | GDB now uses a common structure for symbol information internally. |
| 177 | Minimal symbols (derived from linkage symbols in object files), partial |
| 178 | symbols (from a quick scan of debug information), and full symbols |
| 179 | contain a common subset of information, making it easier to write |
| 180 | shared code that handles any of them. |
| 181 | |
| 182 | * New command line options |
| 183 | |
| 184 | We now accept --silent as an alias for --quiet. |
| 185 | |
| 186 | * Mmalloc licensing |
| 187 | |
| 188 | The memory-mapped-malloc library is now licensed under the GNU Library |
| 189 | General Public License. |
| 190 | |
| 191 | *** Changes in GDB-4.7: |
| 192 | |
| 193 | * Host/native/target split |
| 194 | |
| 195 | GDB has had some major internal surgery to untangle the support for |
| 196 | hosts and remote targets. Now, when you configure GDB for a remote |
| 197 | target, it will no longer load in all of the support for debugging |
| 198 | local programs on the host. When fully completed and tested, this will |
| 199 | ensure that arbitrary host/target combinations are possible. |
| 200 | |
| 201 | The primary conceptual shift is to separate the non-portable code in |
| 202 | GDB into three categories. Host specific code is required any time GDB |
| 203 | is compiled on that host, regardless of the target. Target specific |
| 204 | code relates to the peculiarities of the target, but can be compiled on |
| 205 | any host. Native specific code is everything else: it can only be |
| 206 | built when the host and target are the same system. Child process |
| 207 | handling and core file support are two common `native' examples. |
| 208 | |
| 209 | GDB's use of /proc for controlling Unix child processes is now cleaner. |
| 210 | It has been split out into a single module under the `target_ops' vector, |
| 211 | plus two native-dependent functions for each system that uses /proc. |
| 212 | |
| 213 | * New hosts supported |
| 214 | |
| 215 | HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd |
| 216 | 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd |
| 217 | 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco |
| 218 | |
| 219 | * New targets supported |
| 220 | |
| 221 | Fujitsu SPARClite sparclite-fujitsu-none or sparclite |
| 222 | 68030 and CPU32 m68030-*-*, m68332-*-* |
| 223 | |
| 224 | * New native hosts supported |
| 225 | |
| 226 | 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd |
| 227 | (386bsd is not well tested yet) |
| 228 | 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco |
| 229 | |
| 230 | * New file formats supported |
| 231 | |
| 232 | BFD now supports COFF files for the Zilog Z8000 microprocessor. It |
| 233 | supports reading of `a.out.adobe' object files, which are an a.out |
| 234 | format extended with minimal information about multiple sections. |
| 235 | |
| 236 | * New commands |
| 237 | |
| 238 | `show copying' is the same as the old `info copying'. |
| 239 | `show warranty' is the same as `info warrantee'. |
| 240 | These were renamed for consistency. The old commands continue to work. |
| 241 | |
| 242 | `info handle' is a new alias for `info signals'. |
| 243 | |
| 244 | You can now define pre-command hooks, which attach arbitrary command |
| 245 | scripts to any command. The commands in the hook will be executed |
| 246 | prior to the user's command. You can also create a hook which will be |
| 247 | executed whenever the program stops. See gdb.texinfo. |
| 248 | |
| 249 | * C++ improvements |
| 250 | |
| 251 | We now deal with Cfront style name mangling, and can even extract type |
| 252 | info from mangled symbols. GDB can automatically figure out which |
| 253 | symbol mangling style your C++ compiler uses. |
| 254 | |
| 255 | Calling of methods and virtual functions has been improved as well. |
| 256 | |
| 257 | * Major bug fixes |
| 258 | |
| 259 | The crash that occured when debugging Sun Ansi-C compiled binaries is |
| 260 | fixed. This was due to mishandling of the extra N_SO stabs output |
| 261 | by the compiler. |
| 262 | |
| 263 | We also finally got Ultrix 4.2 running in house, and fixed core file |
| 264 | support, with help from a dozen people on the net. |
| 265 | |
| 266 | John M. Farrell discovered that the reason that single-stepping was so |
| 267 | slow on all of the Mips based platforms (primarily SGI and DEC) was |
| 268 | that we were trying to demangle and lookup a symbol used for internal |
| 269 | purposes on every instruction that was being stepped through. Changing |
| 270 | the name of that symbol so that it couldn't be mistaken for a C++ |
| 271 | mangled symbol sped things up a great deal. |
| 272 | |
| 273 | Rich Pixley sped up symbol lookups in general by getting much smarter |
| 274 | about when C++ symbol mangling is necessary. This should make symbol |
| 275 | completion (TAB on the command line) much faster. It's not as fast as |
| 276 | we'd like, but it's significantly faster than gdb-4.6. |
| 277 | |
| 278 | * AMD 29k support |
| 279 | |
| 280 | A new user controllable variable 'call_scratch_address' can |
| 281 | specify the location of a scratch area to be used when GDB |
| 282 | calls a function in the target. This is necessary because the |
| 283 | usual method of putting the scratch area on the stack does not work |
| 284 | in systems that have separate instruction and data spaces. |
| 285 | |
| 286 | We integrated changes to support the 29k UDI (Universal Debugger |
| 287 | Interface), but discovered at the last minute that we didn't have all |
| 288 | of the appropriate copyright paperwork. We are working with AMD to |
| 289 | resolve this, and hope to have it available soon. |
| 290 | |
| 291 | * Remote interfaces |
| 292 | |
| 293 | We have sped up the remote serial line protocol, especially for targets |
| 294 | with lots of registers. It now supports a new `expedited status' ('T') |
| 295 | message which can be used in place of the existing 'S' status message. |
| 296 | This allows the remote stub to send only the registers that GDB |
| 297 | needs to make a quick decision about single-stepping or conditional |
| 298 | breakpoints, eliminating the need to fetch the entire register set for |
| 299 | each instruction being stepped through. |
| 300 | |
| 301 | The GDB remote serial protocol now implements a write-through cache for |
| 302 | registers, only re-reading the registers if the target has run. |
| 303 | |
| 304 | There is also a new remote serial stub for SPARC processors. You can |
| 305 | find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the |
| 306 | Fujitsu SPARClite processor, but will run on any stand-alone SPARC |
| 307 | processor with a serial port. |
| 308 | |
| 309 | * Configuration |
| 310 | |
| 311 | Configure.in files have become much easier to read and modify. A new |
| 312 | `table driven' format makes it more obvious what configurations are |
| 313 | supported, and what files each one uses. |
| 314 | |
| 315 | * Library changes |
| 316 | |
| 317 | There is a new opcodes library which will eventually contain all of the |
| 318 | disassembly routines and opcode tables. At present, it only contains |
| 319 | Sparc and Z8000 routines. This will allow the assembler, debugger, and |
| 320 | disassembler (binutils/objdump) to share these routines. |
| 321 | |
| 322 | The libiberty library is now copylefted under the GNU Library General |
| 323 | Public License. This allows more liberal use, and was done so libg++ |
| 324 | can use it. This makes no difference to GDB, since the Library License |
| 325 | grants all the rights from the General Public License. |
| 326 | |
| 327 | * Documentation |
| 328 | |
| 329 | The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete |
| 330 | reference to the stabs symbol info used by the debugger. It is (as far |
| 331 | as we know) the only published document on this fascinating topic. We |
| 332 | encourage you to read it, compare it to the stabs information on your |
| 333 | system, and send improvements on the document in general (to |
| 334 | bug-gdb@prep.ai.mit.edu). |
| 335 | |
| 336 | And, of course, many bugs have been fixed. |
| 337 | |
| 338 | |
| 339 | *** Changes in GDB-4.6: |
| 340 | |
| 341 | * Better support for C++ function names |
| 342 | |
| 343 | GDB now accepts as input the "demangled form" of C++ overloaded function |
| 344 | names and member function names, and can do command completion on such names |
| 345 | (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of |
| 346 | single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'. |
| 347 | Make use of command completion, it is your friend. |
| 348 | |
| 349 | GDB also now accepts a variety of C++ mangled symbol formats. They are |
| 350 | the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style. |
| 351 | You can tell GDB which format to use by doing a 'set demangle-style {gnu, |
| 352 | lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo' |
| 353 | for the list of formats. |
| 354 | |
| 355 | * G++ symbol mangling problem |
| 356 | |
| 357 | Recent versions of gcc have a bug in how they emit debugging information for |
| 358 | C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this |
| 359 | directory) can be applied to gcc to fix the problem. Alternatively, if you |
| 360 | can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The |
| 361 | usual symptom is difficulty with setting breakpoints on methods. GDB complains |
| 362 | about the method being non-existent. (We believe that version 2.2.2 of GCC has |
| 363 | this problem.) |
| 364 | |
| 365 | * New 'maintenance' command |
| 366 | |
| 367 | All of the commands related to hacking GDB internals have been moved out of |
| 368 | the main command set, and now live behind the 'maintenance' command. This |
| 369 | can also be abbreviated as 'mt'. The following changes were made: |
| 370 | |
| 371 | dump-me -> maintenance dump-me |
| 372 | info all-breakpoints -> maintenance info breakpoints |
| 373 | printmsyms -> maintenance print msyms |
| 374 | printobjfiles -> maintenance print objfiles |
| 375 | printpsyms -> maintenance print psymbols |
| 376 | printsyms -> maintenance print symbols |
| 377 | |
| 378 | The following commands are new: |
| 379 | |
| 380 | maintenance demangle Call internal GDB demangler routine to |
| 381 | demangle a C++ link name and prints the result. |
| 382 | maintenance print type Print a type chain for a given symbol |
| 383 | |
| 384 | * Change to .gdbinit file processing |
| 385 | |
| 386 | We now read the $HOME/.gdbinit file before processing the argv arguments |
| 387 | (e.g. reading symbol files or core files). This allows global parameters to |
| 388 | be set, which will apply during the symbol reading. The ./.gdbinit is still |
| 389 | read after argv processing. |
| 390 | |
| 391 | * New hosts supported |
| 392 | |
| 393 | Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2 |
| 394 | |
| 395 | Linux support i386-unknown-linux or linux |
| 396 | |
| 397 | We are also including code to support the HP/PA running BSD and HPUX. This |
| 398 | is almost guaranteed not to work, as we didn't have time to test or build it |
| 399 | for this release. We are including it so that the more adventurous (or |
| 400 | masochistic) of you can play with it. We also had major problems with the |
| 401 | fact that the compiler that we got from HP doesn't support the -g option. |
| 402 | It costs extra. |
| 403 | |
| 404 | * New targets supported |
| 405 | |
| 406 | Hitachi H8/300 h8300-hitachi-hms or h8300hms |
| 407 | |
| 408 | * More smarts about finding #include files |
| 409 | |
| 410 | GDB now remembers the compilation directory for all include files, and for |
| 411 | all files from which C is generated (like yacc and lex sources). This |
| 412 | greatly improves GDB's ability to find yacc/lex sources, and include files, |
| 413 | especially if you are debugging your program from a directory different from |
| 414 | the one that contains your sources. |
| 415 | |
| 416 | We also fixed a bug which caused difficulty with listing and setting |
| 417 | breakpoints in include files which contain C code. (In the past, you had to |
| 418 | try twice in order to list an include file that you hadn't looked at before.) |
| 419 | |
| 420 | * Interesting infernals change |
| 421 | |
| 422 | GDB now deals with arbitrary numbers of sections, where the symbols for each |
| 423 | section must be relocated relative to that section's landing place in the |
| 424 | target's address space. This work was needed to support ELF with embedded |
| 425 | stabs used by Solaris-2.0. |
| 426 | |
| 427 | * Bug fixes (of course!) |
| 428 | |
| 429 | There have been loads of fixes for the following things: |
| 430 | mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k, |
| 431 | i960, stabs, DOS(GO32), procfs, etc... |
| 432 | |
| 433 | See the ChangeLog for details. |
| 434 | |
| 435 | *** Changes in GDB-4.5: |
| 436 | |
| 437 | * New machines supported (host and target) |
| 438 | |
| 439 | IBM RS6000 running AIX rs6000-ibm-aix or rs6000 |
| 440 | |
| 441 | SGI Irix-4.x mips-sgi-irix4 or iris4 |
| 442 | |
| 443 | * New malloc package |
| 444 | |
| 445 | GDB now uses a new memory manager called mmalloc, based on gmalloc. |
| 446 | Mmalloc is capable of handling mutiple heaps of memory. It is also |
| 447 | capable of saving a heap to a file, and then mapping it back in later. |
| 448 | This can be used to greatly speedup the startup of GDB by using a |
| 449 | pre-parsed symbol table which lives in a mmalloc managed heap. For |
| 450 | more details, please read mmalloc/mmalloc.texi. |
| 451 | |
| 452 | * info proc |
| 453 | |
| 454 | The 'info proc' command (SVR4 only) has been enhanced quite a bit. See |
| 455 | 'help info proc' for details. |
| 456 | |
| 457 | * MIPS ecoff symbol table format |
| 458 | |
| 459 | The code that reads MIPS symbol table format is now supported on all hosts. |
| 460 | Thanks to MIPS for releasing the sym.h and symconst.h files to make this |
| 461 | possible. |
| 462 | |
| 463 | * File name changes for MS-DOS |
| 464 | |
| 465 | Many files in the config directories have been renamed to make it easier to |
| 466 | support GDB on MS-DOSe systems (which have very restrictive file name |
| 467 | conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32 |
| 468 | environment) is close to working but has some remaining problems. Note |
| 469 | that debugging of DOS programs is not supported, due to limitations |
| 470 | in the ``operating system'', but it can be used to host cross-debugging. |
| 471 | |
| 472 | * Cross byte order fixes |
| 473 | |
| 474 | Many fixes have been made to support cross debugging of Sparc and MIPS |
| 475 | targets from hosts whose byte order differs. |
| 476 | |
| 477 | * New -mapped and -readnow options |
| 478 | |
| 479 | If memory-mapped files are available on your system through the 'mmap' |
| 480 | system call, you can use the -mapped option on the `file' or |
| 481 | `symbol-file' commands to cause GDB to write the symbols from your |
| 482 | program into a reusable file. If the program you are debugging is |
| 483 | called `/path/fred', the mapped symbol file will be `./fred.syms'. |
| 484 | Future GDB debugging sessions will notice the presence of this file, |
| 485 | and will quickly map in symbol information from it, rather than reading |
| 486 | the symbol table from the executable program. Using the '-mapped' |
| 487 | option in a GDB `file' or `symbol-file' command has the same effect as |
| 488 | starting GDB with the '-mapped' command-line option. |
| 489 | |
| 490 | You can cause GDB to read the entire symbol table immediately by using |
| 491 | the '-readnow' option with any of the commands that load symbol table |
| 492 | information (or on the GDB command line). This makes the command |
| 493 | slower, but makes future operations faster. |
| 494 | |
| 495 | The -mapped and -readnow options are typically combined in order to |
| 496 | build a `fred.syms' file that contains complete symbol information. |
| 497 | A simple GDB invocation to do nothing but build a `.syms' file for future |
| 498 | use is: |
| 499 | |
| 500 | gdb -batch -nx -mapped -readnow programname |
| 501 | |
| 502 | The `.syms' file is specific to the host machine on which GDB is run. |
| 503 | It holds an exact image of GDB's internal symbol table. It cannot be |
| 504 | shared across multiple host platforms. |
| 505 | |
| 506 | * longjmp() handling |
| 507 | |
| 508 | GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and |
| 509 | siglongjmp() without losing control. This feature has not yet been ported to |
| 510 | all systems. It currently works on many 386 platforms, all MIPS-based |
| 511 | platforms (SGI, DECstation, etc), and Sun3/4. |
| 512 | |
| 513 | * Solaris 2.0 |
| 514 | |
| 515 | Preliminary work has been put in to support the new Solaris OS from Sun. At |
| 516 | this time, it can control and debug processes, but it is not capable of |
| 517 | reading symbols. |
| 518 | |
| 519 | * Bug fixes |
| 520 | |
| 521 | As always, many many bug fixes. The major areas were with g++, and mipsread. |
| 522 | People using the MIPS-based platforms should experience fewer mysterious |
| 523 | crashes and trashed symbol tables. |
| 524 | |
| 525 | *** Changes in GDB-4.4: |
| 526 | |
| 527 | * New machines supported (host and target) |
| 528 | |
| 529 | SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco |
| 530 | (except core files) |
| 531 | BSD Reno on Vax vax-dec-bsd |
| 532 | Ultrix on Vax vax-dec-ultrix |
| 533 | |
| 534 | * New machines supported (target) |
| 535 | |
| 536 | AMD 29000 embedded, using EBMON a29k-none-none |
| 537 | |
| 538 | * C++ support |
| 539 | |
| 540 | GDB continues to improve its handling of C++. `References' work better. |
| 541 | The demangler has also been improved, and now deals with symbols mangled as |
| 542 | per the Annotated C++ Reference Guide. |
| 543 | |
| 544 | GDB also now handles `stabs' symbol information embedded in MIPS |
| 545 | `ecoff' symbol tables. Since the ecoff format was not easily |
| 546 | extensible to handle new languages such as C++, this appeared to be a |
| 547 | good way to put C++ debugging info into MIPS binaries. This option |
| 548 | will be supported in the GNU C compiler, version 2, when it is |
| 549 | released. |
| 550 | |
| 551 | * New features for SVR4 |
| 552 | |
| 553 | GDB now handles SVR4 shared libraries, in the same fashion as SunOS |
| 554 | shared libraries. Debugging dynamically linked programs should present |
| 555 | only minor differences from debugging statically linked programs. |
| 556 | |
| 557 | The `info proc' command will print out information about any process |
| 558 | on an SVR4 system (including the one you are debugging). At the moment, |
| 559 | it prints the address mappings of the process. |
| 560 | |
| 561 | If you bring up GDB on another SVR4 system, please send mail to |
| 562 | bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any). |
| 563 | |
| 564 | * Better dynamic linking support in SunOS |
| 565 | |
| 566 | Reading symbols from shared libraries which contain debugging symbols |
| 567 | now works properly. However, there remain issues such as automatic |
| 568 | skipping of `transfer vector' code during function calls, which |
| 569 | make it harder to debug code in a shared library, than to debug the |
| 570 | same code linked statically. |
| 571 | |
| 572 | * New Getopt |
| 573 | |
| 574 | GDB is now using the latest `getopt' routines from the FSF. This |
| 575 | version accepts the -- prefix for options with long names. GDB will |
| 576 | continue to accept the old forms (-option and +option) as well. |
| 577 | Various single letter abbreviations for options have been explicity |
| 578 | added to the option table so that they won't get overshadowed in the |
| 579 | future by other options that begin with the same letter. |
| 580 | |
| 581 | * Bugs fixed |
| 582 | |
| 583 | The `cleanup_undefined_types' bug that many of you noticed has been squashed. |
| 584 | Many assorted bugs have been handled. Many more remain to be handled. |
| 585 | See the various ChangeLog files (primarily in gdb and bfd) for details. |
| 586 | |
| 587 | |
| 588 | *** Changes in GDB-4.3: |
| 589 | |
| 590 | * New machines supported (host and target) |
| 591 | |
| 592 | Amiga 3000 running Amix m68k-cbm-svr4 or amix |
| 593 | NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000 |
| 594 | Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88 |
| 595 | |
| 596 | * Almost SCO Unix support |
| 597 | |
| 598 | We had hoped to support: |
| 599 | SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco |
| 600 | (except for core file support), but we discovered very late in the release |
| 601 | that it has problems with process groups that render gdb unusable. Sorry |
| 602 | about that. I encourage people to fix it and post the fixes. |
| 603 | |
| 604 | * Preliminary ELF and DWARF support |
| 605 | |
| 606 | GDB can read ELF object files on System V Release 4, and can handle |
| 607 | debugging records for C, in DWARF format, in ELF files. This support |
| 608 | is preliminary. If you bring up GDB on another SVR4 system, please |
| 609 | send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were |
| 610 | reqired (if any). |
| 611 | |
| 612 | * New Readline |
| 613 | |
| 614 | GDB now uses the latest `readline' library. One user-visible change |
| 615 | is that two tabs will list possible command completions, which previously |
| 616 | required typing M-? (meta-question mark, or ESC ?). |
| 617 | |
| 618 | * Bugs fixed |
| 619 | |
| 620 | The `stepi' bug that many of you noticed has been squashed. |
| 621 | Many bugs in C++ have been handled. Many more remain to be handled. |
| 622 | See the various ChangeLog files (primarily in gdb and bfd) for details. |
| 623 | |
| 624 | * State of the MIPS world (in case you wondered): |
| 625 | |
| 626 | GDB can understand the symbol tables emitted by the compilers |
| 627 | supplied by most vendors of MIPS-based machines, including DEC. These |
| 628 | symbol tables are in a format that essentially nobody else uses. |
| 629 | |
| 630 | Some versions of gcc come with an assembler post-processor called |
| 631 | mips-tfile. This program is required if you want to do source-level |
| 632 | debugging of gcc-compiled programs. I believe FSF does not ship |
| 633 | mips-tfile with gcc version 1, but it will eventually come with gcc |
| 634 | version 2. |
| 635 | |
| 636 | Debugging of g++ output remains a problem. g++ version 1.xx does not |
| 637 | really support it at all. (If you're lucky, you should be able to get |
| 638 | line numbers and stack traces to work, but no parameters or local |
| 639 | variables.) With some work it should be possible to improve the |
| 640 | situation somewhat. |
| 641 | |
| 642 | When gcc version 2 is released, you will have somewhat better luck. |
| 643 | However, even then you will get confusing results for inheritance and |
| 644 | methods. |
| 645 | |
| 646 | We will eventually provide full debugging of g++ output on |
| 647 | DECstations. This will probably involve some kind of stabs-in-ecoff |
| 648 | encapulation, but the details have not been worked out yet. |
| 649 | |
| 650 | |
| 651 | *** Changes in GDB-4.2: |
| 652 | |
| 653 | * Improved configuration |
| 654 | |
| 655 | Only one copy of `configure' exists now, and it is not self-modifying. |
| 656 | Porting BFD is simpler. |
| 657 | |
| 658 | * Stepping improved |
| 659 | |
| 660 | The `step' and `next' commands now only stop at the first instruction |
| 661 | of a source line. This prevents the multiple stops that used to occur |
| 662 | in switch statements, for-loops, etc. `Step' continues to stop if a |
| 663 | function that has debugging information is called within the line. |
| 664 | |
| 665 | * Bug fixing |
| 666 | |
| 667 | Lots of small bugs fixed. More remain. |
| 668 | |
| 669 | * New host supported (not target) |
| 670 | |
| 671 | Intel 386 PC clone running Mach i386-none-mach |
| 672 | |
| 673 | |
| 674 | *** Changes in GDB-4.1: |
| 675 | |
| 676 | * Multiple source language support |
| 677 | |
| 678 | GDB now has internal scaffolding to handle several source languages. |
| 679 | It determines the type of each source file from its filename extension, |
| 680 | and will switch expression parsing and number formatting to match the |
| 681 | language of the function in the currently selected stack frame. |
| 682 | You can also specifically set the language to be used, with |
| 683 | `set language c' or `set language modula-2'. |
| 684 | |
| 685 | * GDB and Modula-2 |
| 686 | |
| 687 | GDB now has preliminary support for the GNU Modula-2 compiler, |
| 688 | currently under development at the State University of New York at |
| 689 | Buffalo. Development of both GDB and the GNU Modula-2 compiler will |
| 690 | continue through the fall of 1991 and into 1992. |
| 691 | |
| 692 | Other Modula-2 compilers are currently not supported, and attempting to |
| 693 | debug programs compiled with them will likely result in an error as the |
| 694 | symbol table is read. Feel free to work on it, though! |
| 695 | |
| 696 | There are hooks in GDB for strict type checking and range checking, |
| 697 | in the `Modula-2 philosophy', but they do not currently work. |
| 698 | |
| 699 | * set write on/off |
| 700 | |
| 701 | GDB can now write to executable and core files (e.g. patch |
| 702 | a variable's value). You must turn this switch on, specify |
| 703 | the file ("exec foo" or "core foo"), *then* modify it, e.g. |
| 704 | by assigning a new value to a variable. Modifications take |
| 705 | effect immediately. |
| 706 | |
| 707 | * Automatic SunOS shared library reading |
| 708 | |
| 709 | When you run your program, GDB automatically determines where its |
| 710 | shared libraries (if any) have been loaded, and reads their symbols. |
| 711 | The `share' command is no longer needed. This also works when |
| 712 | examining core files. |
| 713 | |
| 714 | * set listsize |
| 715 | |
| 716 | You can specify the number of lines that the `list' command shows. |
| 717 | The default is 10. |
| 718 | |
| 719 | * New machines supported (host and target) |
| 720 | |
| 721 | SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris |
| 722 | Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news |
| 723 | Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3 |
| 724 | |
| 725 | * New hosts supported (not targets) |
| 726 | |
| 727 | IBM RT/PC: romp-ibm-aix or rtpc |
| 728 | |
| 729 | * New targets supported (not hosts) |
| 730 | |
| 731 | AMD 29000 embedded with COFF a29k-none-coff |
| 732 | AMD 29000 embedded with a.out a29k-none-aout |
| 733 | Ultracomputer remote kernel debug a29k-nyu-kern |
| 734 | |
| 735 | * New remote interfaces |
| 736 | |
| 737 | AMD 29000 Adapt |
| 738 | AMD 29000 Minimon |
| 739 | |
| 740 | |
| 741 | *** Changes in GDB-4.0: |
| 742 | |
| 743 | * New Facilities |
| 744 | |
| 745 | Wide output is wrapped at good places to make the output more readable. |
| 746 | |
| 747 | Gdb now supports cross-debugging from a host machine of one type to a |
| 748 | target machine of another type. Communication with the target system |
| 749 | is over serial lines. The ``target'' command handles connecting to the |
| 750 | remote system; the ``load'' command will download a program into the |
| 751 | remote system. Serial stubs for the m68k and i386 are provided. Gdb |
| 752 | also supports debugging of realtime processes running under VxWorks, |
| 753 | using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger |
| 754 | stub on the target system. |
| 755 | |
| 756 | New CPUs supported include the AMD 29000 and Intel 960. |
| 757 | |
| 758 | GDB now reads object files and symbol tables via a ``binary file'' |
| 759 | library, which allows a single copy of GDB to debug programs of multiple |
| 760 | object file types such as a.out and coff. |
| 761 | |
| 762 | There is now a GDB reference card in "doc/refcard.tex". (Make targets |
| 763 | refcard.dvi and refcard.ps are available to format it). |
| 764 | |
| 765 | |
| 766 | * Control-Variable user interface simplified |
| 767 | |
| 768 | All variables that control the operation of the debugger can be set |
| 769 | by the ``set'' command, and displayed by the ``show'' command. |
| 770 | |
| 771 | For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>. |
| 772 | ``Show prompt'' produces the response: |
| 773 | Gdb's prompt is new-gdb=>. |
| 774 | |
| 775 | What follows are the NEW set commands. The command ``help set'' will |
| 776 | print a complete list of old and new set commands. ``help set FOO'' |
| 777 | will give a longer description of the variable FOO. ``show'' will show |
| 778 | all of the variable descriptions and their current settings. |
| 779 | |
| 780 | confirm on/off: Enables warning questions for operations that are |
| 781 | hard to recover from, e.g. rerunning the program while |
| 782 | it is already running. Default is ON. |
| 783 | |
| 784 | editing on/off: Enables EMACS style command line editing |
| 785 | of input. Previous lines can be recalled with |
| 786 | control-P, the current line can be edited with control-B, |
| 787 | you can search for commands with control-R, etc. |
| 788 | Default is ON. |
| 789 | |
| 790 | history filename NAME: NAME is where the gdb command history |
| 791 | will be stored. The default is .gdb_history, |
| 792 | or the value of the environment variable |
| 793 | GDBHISTFILE. |
| 794 | |
| 795 | history size N: The size, in commands, of the command history. The |
| 796 | default is 256, or the value of the environment variable |
| 797 | HISTSIZE. |
| 798 | |
| 799 | history save on/off: If this value is set to ON, the history file will |
| 800 | be saved after exiting gdb. If set to OFF, the |
| 801 | file will not be saved. The default is OFF. |
| 802 | |
| 803 | history expansion on/off: If this value is set to ON, then csh-like |
| 804 | history expansion will be performed on |
| 805 | command line input. The default is OFF. |
| 806 | |
| 807 | radix N: Sets the default radix for input and output. It can be set |
| 808 | to 8, 10, or 16. Note that the argument to "radix" is interpreted |
| 809 | in the current radix, so "set radix 10" is always a no-op. |
| 810 | |
| 811 | height N: This integer value is the number of lines on a page. Default |
| 812 | is 24, the current `stty rows'' setting, or the ``li#'' |
| 813 | setting from the termcap entry matching the environment |
| 814 | variable TERM. |
| 815 | |
| 816 | width N: This integer value is the number of characters on a line. |
| 817 | Default is 80, the current `stty cols'' setting, or the ``co#'' |
| 818 | setting from the termcap entry matching the environment |
| 819 | variable TERM. |
| 820 | |
| 821 | Note: ``set screensize'' is obsolete. Use ``set height'' and |
| 822 | ``set width'' instead. |
| 823 | |
| 824 | print address on/off: Print memory addresses in various command displays, |
| 825 | such as stack traces and structure values. Gdb looks |
| 826 | more ``symbolic'' if you turn this off; it looks more |
| 827 | ``machine level'' with it on. Default is ON. |
| 828 | |
| 829 | print array on/off: Prettyprint arrays. New convenient format! Default |
| 830 | is OFF. |
| 831 | |
| 832 | print demangle on/off: Print C++ symbols in "source" form if on, |
| 833 | "raw" form if off. |
| 834 | |
| 835 | print asm-demangle on/off: Same, for assembler level printouts |
| 836 | like instructions. |
| 837 | |
| 838 | print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF. |
| 839 | |
| 840 | |
| 841 | * Support for Epoch Environment. |
| 842 | |
| 843 | The epoch environment is a version of Emacs v18 with windowing. One |
| 844 | new command, ``inspect'', is identical to ``print'', except that if you |
| 845 | are running in the epoch environment, the value is printed in its own |
| 846 | window. |
| 847 | |
| 848 | |
| 849 | * Support for Shared Libraries |
| 850 | |
| 851 | GDB can now debug programs and core files that use SunOS shared libraries. |
| 852 | Symbols from a shared library cannot be referenced |
| 853 | before the shared library has been linked with the program (this |
| 854 | happens after you type ``run'' and before the function main() is entered). |
| 855 | At any time after this linking (including when examining core files |
| 856 | from dynamically linked programs), gdb reads the symbols from each |
| 857 | shared library when you type the ``sharedlibrary'' command. |
| 858 | It can be abbreviated ``share''. |
| 859 | |
| 860 | sharedlibrary REGEXP: Load shared object library symbols for files |
| 861 | matching a unix regular expression. No argument |
| 862 | indicates to load symbols for all shared libraries. |
| 863 | |
| 864 | info sharedlibrary: Status of loaded shared libraries. |
| 865 | |
| 866 | |
| 867 | * Watchpoints |
| 868 | |
| 869 | A watchpoint stops execution of a program whenever the value of an |
| 870 | expression changes. Checking for this slows down execution |
| 871 | tremendously whenever you are in the scope of the expression, but is |
| 872 | quite useful for catching tough ``bit-spreader'' or pointer misuse |
| 873 | problems. Some machines such as the 386 have hardware for doing this |
| 874 | more quickly, and future versions of gdb will use this hardware. |
| 875 | |
| 876 | watch EXP: Set a watchpoint (breakpoint) for an expression. |
| 877 | |
| 878 | info watchpoints: Information about your watchpoints. |
| 879 | |
| 880 | delete N: Deletes watchpoint number N (same as breakpoints). |
| 881 | disable N: Temporarily turns off watchpoint number N (same as breakpoints). |
| 882 | enable N: Re-enables watchpoint number N (same as breakpoints). |
| 883 | |
| 884 | |
| 885 | * C++ multiple inheritance |
| 886 | |
| 887 | When used with a GCC version 2 compiler, GDB supports multiple inheritance |
| 888 | for C++ programs. |
| 889 | |
| 890 | * C++ exception handling |
| 891 | |
| 892 | Gdb now supports limited C++ exception handling. Besides the existing |
| 893 | ability to breakpoint on an exception handler, gdb can breakpoint on |
| 894 | the raising of an exception (before the stack is peeled back to the |
| 895 | handler's context). |
| 896 | |
| 897 | catch FOO: If there is a FOO exception handler in the dynamic scope, |
| 898 | set a breakpoint to catch exceptions which may be raised there. |
| 899 | Multiple exceptions (``catch foo bar baz'') may be caught. |
| 900 | |
| 901 | info catch: Lists all exceptions which may be caught in the |
| 902 | current stack frame. |
| 903 | |
| 904 | |
| 905 | * Minor command changes |
| 906 | |
| 907 | The command ``call func (arg, arg, ...)'' now acts like the print |
| 908 | command, except it does not print or save a value if the function's result |
| 909 | is void. This is similar to dbx usage. |
| 910 | |
| 911 | The ``up'' and ``down'' commands now always print the frame they end up |
| 912 | at; ``up-silently'' and `down-silently'' can be used in scripts to change |
| 913 | frames without printing. |
| 914 | |
| 915 | * New directory command |
| 916 | |
| 917 | 'dir' now adds directories to the FRONT of the source search path. |
| 918 | The path starts off empty. Source files that contain debug information |
| 919 | about the directory in which they were compiled can be found even |
| 920 | with an empty path; Sun CC and GCC include this information. If GDB can't |
| 921 | find your source file in the current directory, type "dir .". |
| 922 | |
| 923 | * Configuring GDB for compilation |
| 924 | |
| 925 | For normal use, type ``./configure host''. See README or gdb.texinfo |
| 926 | for more details. |
| 927 | |
| 928 | GDB now handles cross debugging. If you are remotely debugging between |
| 929 | two different machines, type ``./configure host -target=targ''. |
| 930 | Host is the machine where GDB will run; targ is the machine |
| 931 | where the program that you are debugging will run. |