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Diffstat (limited to 'contrib/gdb/gdb/TODO')
| -rw-r--r-- | contrib/gdb/gdb/TODO | 572 |
1 files changed, 226 insertions, 346 deletions
diff --git a/contrib/gdb/gdb/TODO b/contrib/gdb/gdb/TODO index fcbcd16..ea46e9b 100644 --- a/contrib/gdb/gdb/TODO +++ b/contrib/gdb/gdb/TODO @@ -1,470 +1,350 @@ If you find inaccuracies in this list, please send mail to -bug-gdb@prep.ai.mit.edu. If you would like to work on any of these, -you should consider sending mail to the same address, to find out -whether anyone else is working on it. +gdb-patches@sources.redhat.com. If you would like to work on any +of these, you should consider sending mail to the same address, to +find out whether anyone else is working on it. -General To Do List ------------------- -This list is probably not up to date, and opinions vary about the -importance or even desirability of some of the items. + GDB 5.1 - Fixes + =============== -Add an "info bfd" command that displays supported object formats, -similarly to objdump -i. +Below is a list of problems identified during the GDB 5.0 release +cycle. People hope to have these problems fixed in 5.1. -START_INFERIOR_TRAPS_EXPECTED need never be defined to 2, since that -is its default value. Clean this up. +-- -It should be possible to use symbols from shared libraries before we know -exactly where the libraries will be loaded. E.g. "b perror" before running -the program. This could maybe be done as an extension of the "breakpoint -re-evaluation" after new symbols are loaded. +Wow, three bug reports for the same problem in one day! We should +probably make fixing this a real priority :-). -Make single_step() insert and remove breakpoints in one operation. +Anyway, thanks for reporting. -Speed up single stepping by avoiding extraneous ptrace calls. +The following patch will fix the problems with setting breakpoints in +dynamically loaded objects: -Speed up single stepping by not inserting and removing breakpoints -each time the inferior starts and stops. + http://sources.redhat.com/ml/gdb-patches/2000-05/msg00230.html -Breakpoints should not be inserted and deleted all the time. Only the -one(s) there should be removed when we have to step over one. Support -breakpoints that don't have to be removed to step over them. +This patch isn't checked in yet (ping Michael/JimB), but I hope this +will be in the next GDB release. -Update gdbint.texinfo to include doc on the directory structure and -the various tricks of building gdb. +There should really be a test in the testsuite for this problem, since +it keeps coming up :-(. Any volunteers? -Do a tutorial in gdb.texinfo on how to do simple things in gdb. -E.g. how to set a breakpoint that just prints something and continues. -How to break on aborts. Etc. +Mark -Provide "voodoo" debugging of core files. This creates a zombie -process as a child of the debugger, and loads it up with the data, -stack, and regs of the core file. This allows you to call functions -in the executable, to manipulate the data in the core file. +-- -GDB reopens the source file on every line, as you "next" through it. + GDB 5.1 - New features + ====================== -Referencing the vtbl member of a struct doesn't work. It prints OK -if you print the struct, but it gets 0 if you try to deref it. +The following new features should be included in 5.1. -Persistent command history: A feature where you could save off a list -of the commands you did, so you can edit it into something that will bring -the target to the same place every time you source it. -This would also be useful for automated fast watchpointing; if you go -past the place where it watchpoints, you just start it over again and -do it more carefully. +-- -Deal with the SunOS 4.0 and 4.1.1 ptrace bug that loses the registers if -the stack is paged out. + GDB 5.1 - Cleanups + ================== -Finish the C++ exception handling stub routines. Lint points them out -as unused statics functions. +The following code cleanups will hopefully be applied to GDB 5.1. -Perhaps "i source" should take an argument like that of "list". +-- -See if core-aout.c's fetch_core_registers can be used on more machines. -E.g. MIPS (mips-xdep.c). + GDB 5.1 - Known Problems + ======================== -unpack_double() does not handle IEEE float on the target unless the host -is also IEEE. Death on a vax. +-- -Set up interface between GDB and INFO so that you can hop into interactive -INFO and back out again. When running under Emacs, should use Emacs -info, else fork the info program. Installation of GDB should install -its texinfo files into the info tree automagically, including the readline -texinfo files. +z8k -"help address" ought to find the "help set print address" entry. +The z8k has suffered bit rot and is known to not build. The problem +was occuring in the opcodes directory. -Remove the VTBL internal guts from printouts of C++ structs, unless -vtblprint is set. +-- -Remove "at 0xnnnn" from the "b foo" response, if `print address off' and if -it matches the source line indicated. +The BFD directory requires bug-fixed AUTOMAKE et.al. -The prompt at end of screen should accept space as well as CR. +AUTOMAKE 1.4 incorrectly set the TEXINPUTS environment variable. It +contained the full path to texinfo.tex when it should have only +contained the directory. The bug has been fixed in the current +AUTOMAKE sources. Automake snapshots can be found in: + ftp://sources.redhat.com/pub/gdb/infrastructure +and ftp://sources.redhat.com/pub/binutils -Check STORE_RETURN_VALUE on all architectures. Check near it in tm-sparc.h -for other bogosities. +-- -Check for storage leaks in GDB, I'm sure there are a lot! +Solaris 8 x86 CURSES_H problem +http://sources.redhat.com/ml/gdb/2000-07/msg00038.html -vtblprint of a vtbl should demangle the names it's printing. +The original problem was worked around with: -Backtrace should point out what the currently selected frame is, in -its display, perhaps showing "@3 foo (bar, ...)" or ">3 foo (bar, -...)" rather than "#3 foo (bar, ...)". + 2000-06-06 Michael Snyder <msnyder@cygnus.com> -"i program" should work for core files, and display more info, like what -actually caused it to die. + * configure.in: Enable autoconf to find curses.h on Solaris 2.8. + * configure: Regenerate. -"x/10i" should shorten the long name, if any, on subsequent lines. +When building both GDB and SID using the same source tree the problem +will still occure. sid/component/configure.in mis-configures +<curses.h> and leaves wrong information in the config cache. -Check through the code for FIXME comments and fix them. dbxread.c, -blockframe.c, and plenty more. (I count 634 as of 940621 - sts) +-- -"next" over a function that longjumps, never stops until next time you happen -to get to that spot by accident. E.g. "n" over execute_command which has -an error. + GDB 5.2 - Fixes + =============== -"set zeroprint off", don't bother printing members of structs which -are entirely zero. Useful for those big structs with few useful -members. +-- -GDB does four ioctl's for every command, probably switching terminal modes -to/from inferior or for readline or something. + GDB 5.2 - New features + ====================== -terminal_ours versus terminal_inferior: cache state. Switch should be a noop -if the state is the same, too. +-- -ptype $i6 = void??! +GCC 3.0 ABI support (but hopefully sooner...). -Clean up invalid_float handling so gdb doesn't coredump when it tries to -access a NaN. While this might work on SPARC, other machines are not -configured right. +-- -"b value_at ; commands ; continue ; end" stops EVERY OTHER TIME! -Then once you enter a command, it does the command, runs two more -times, and then stops again! Bizarre... (This behaviour has been -modified, but it is not yet 100% predictable when e.g. the commands -call functions in the child, and while there, the child is interrupted -with a signal, or hits a breakpoint.) +Objective C/C++ support (but hopefully sooner...). -help completion, help history should work. +-- -Check that we can handle stack trace through varargs AND alloca in same -function, on 29K. +Import of readline 4.2 -wait_for_inferior loops forever if wait() gives it an error. +-- -"i frame" shows wrong "arglist at" location, doesn't show where the args -should be found, only their actual values. + GDB 5.2 - Cleanups + ================== -There should be a way for "set" commands to validate the new setting -before it takes effect. +The following cleanups have been identified as part of GDB 5.2. -A mess of floating point opcodes are missing from sparc-opcode.h. -Also, a little program should test the table for bits that are -overspecified or underspecified. E.g. if the must-be-ones bits -and the must-be-zeroes bits leave some fields unexamined, and the format -string leaves them unprinted, then point this out. If multiple -non-alias patterns match, point this out too. Finally, there should -be a sparc-optest.s file that tries each pattern out. This file -should end up coming back the same (modulo transformation comments) -if fed to "gas" then the .o is fed to gdb for disassembly. +-- -Eliminate all the core_file_command's in all the xdep files. -Eliminate separate declarations of registers[] everywhere. +Remove old code that does not use ui_out functions and all the related +"ifdef"s. This also allows the elimination of -DUI_OUT from +Makefile.in and configure.in. -"ena d" is ambiguous, why? "ena delete" seems to think it is a command! +-- -Perhaps move the tdep, xdep, and nat files, into the config -subdirectories. If not, at least straighten out their names so that -they all start with the machine name. +Compiler warnings. -inferior_status should include stop_print_frame. It won't need to be -reset in wait_for_inferior after bpstat_stop_status call, then. +Eliminate warnings for all targets on at least one host for one of the +-W flags. Flags up for debate include: -Wswitch -Wcomment -trigraphs +-Wtrigraphs -Wunused-function -Wunused-label -Wunused-variable +-Wunused-value -Wchar-subscripts -Wtraditional -Wshadow -Wcast-qual +-Wcast-align -Wwrite-strings -Wconversion -Wstrict-prototypes +-Wmissing-prototypes -Wmissing-declarations -Wredundant-decls +-Woverloaded-virtual -Winline -i line VAR produces "Line number not known for symbol ``var''.". I -thought we were stashing that info now! +-- -We should be able to write to random files at hex offsets like adb. +Deprecate, if not delete, the following: -Make "target xxx" command interruptible. + register[] + register_valid[] + REGISTER_BYTE() + Replaced by, on the target side + supply_register() + and on core-gdb side: + {read,write}_register_gen() + Remote.c will need to use something + other than REGISTER_BYTE() and + REGISTER_RAW_SIZE() when unpacking + [gG] packets. -Handle add_file with separate text, data, and bss addresses. Maybe -handle separate addresses for each segment in the object file? + STORE_PSEUDO_REGISTER + FETCH_PSEUDO_REGISTER + Now handed by the methods + gdbarch_{read,write}_register() + which sits between core GDB and + the register cache. -Handle free_named_symtab to cope with multiply-loaded object files -in a dynamic linking environment. Should remember the last copy loaded, -but not get too snowed if it finds references to the older copy. + REGISTER_CONVERTIBLE + REGISTER_CONVERT_TO_RAW + REGISTER_CONVERT_TO_VIRTUAL + I think these three are redundant. + gdbarch_register_{read,write} can + do any conversion it likes. -Generalize and Standardize the RPC interface to a target program, -improve it beyond the "ptrace" interface, and see if it can become a -standard for remote debugging. (This is talking about the vxworks -interface. Seems unlikely to me that there will be "a standard" for -remote debugging anytime soon --kingdon, 8 Nov 1994). + REGISTER_VIRTUAL_SIZE + MAX_REGISTER_VIRTUAL_SIZE + REGISTER_VIRTUAL_TYPE + I think these can be replaced by + the pair: + FRAME_REGISTER_TYPE(frame, regnum) + REGISTER_TYPE(regnum) -Remove all references to: - text_offset - data_offset - text_data_start - text_end - exec_data_offset - ... -now that we have BFD. All remaining are in machine dependent files. + DO_REGISTERS_INFO + Replace with + FRAME_REGISTER_INFO (frame, ...) -When quitting with a running program, if a core file was previously -examined, you get "Couldn't read float regs from core file"...if -indeed it can't. generic_mourn_inferior... + REGISTER_SIM_REGNO() + If nothing else rename this so that + how it relates to rawreg and the + regnum is clear. -Have remote targets give a warning on a signal argument to -target_resume. Or better yet, extend the protocols so that it works -like it does on the Unix-like systems. + REGISTER_BYTES + The size of the cache can be computed + on the fly. -Sort help and info output. + IS_TRAPPED_INTERNALVAR + The pseudo registers should eventually make + this redundant. -Re-organize help categories into things that tend to fit on a screen -and hang together. +-- -renote-nindy.c handles interrupts poorly; it error()s out of badly -chosen places, e.g. leaving current_frame zero, which causes core dumps -on the next command. +Obsolete the targets: -Add in commands like ADB's for searching for patterns, etc. We should -be able to examine and patch raw unsymboled binaries as well in gdb as -we can in adb. (E.g. increase the timeout in /bin/login without source). +arm*-wince-pe +mips*-*-pe +sh*-*-pe -Those xdep files that call register_addr without defining it are -probably simply broken. When reconfiguring this part of gdb, I could -only make guesses about how to redo some of those files, and I -probably guessed wrong, or left them "for later" when I have a -machine that can attempt to build them. +-- -When doing "step" or "next", if a few lines of source are skipped between -the previous line and the current one, print those lines, not just the -last line of a multiline statement. +Obsolete the protocols: -When searching for C++ superclasses in value_cast in valops.c, we must -not search the "fields", only the "superclasses". There might be a -struct with a field name that matches the superclass name. This can -happen when the struct was defined before the superclass (before the -name became a typedef). +RDB? -Handling of "&" address-of operator needs some serious overhaul -for ANSI C and consistency on arrays and functions. - For "float point[15];": -ptype &point[4] ==> Attempt to take address of non-lvalue. - For "char *malloc();": -ptype malloc ==> "char *()"; should be same as -ptype &malloc ==> "char *(*)()" -call printf ("%x\n", malloc) ==> weird value, should be same as -call printf ("%x\n", &malloc) ==> correct value +``As of version 5.3, WindRiver has removed the RDB server (RDB +protocol support is built into gdb).'' -- Till. -Fix dbxread.c symbol reading in the presence of interrupts. It -currently leaves a cleanup to blow away the entire symbol table when a -QUIT occurs. (What's wrong with that? -kingdon, 28 Oct 1993). +-- -Mipsread.c reads include files depth-first, because the dependencies -in the psymtabs are way too inclusive (it seems to me). Figure out what -really depends on what, to avoid recursing 20 or 30 times while reading -real symtabs. +Restructure gdb directory tree so that it avoids any 8.3 and 14 +filename problems. -value_add() should be subtracting the lower bound of arrays, if known, -and possibly checking against the upper bound for error reporting. +-- -mipsread.c symbol table allocation and deallocation should be checked. -My suspicion is that it's full of memory leaks. +Convert GDB build process to AUTOMAKE. -SunOS should have a target_lookup_symbol() for common'd things allocated -by the shared library linker ld.so. +See also sub-directory configure below. -When listing source lines, check for a preceding \n, to verify that -the file hasn't changed out from under us. +The current convention is (kind of) to use $(<header>_h) in all +dependency lists. It isn't done in a consistent way. -When listing source lines, eat leading whitespace corresponding to the -line-number prefix we print. This avoids long lines wrapping. +-- -mipsread.c needs to check for old symtabs and psymtabs for the same -files, the way it happens for dbxread.c and coffread.c, for VxWorks -incremental symbol table reloading. + GDB 5.2 - Known Problems + ======================== -Get all the remote systems (where the protocol allows it) to be able to -stop the remote system when the GDB user types ^C (like remote.c -does). For ebmon, use ^Ak. - -Possible feature: A version of the "disassemble" command which shows -both source and assembly code ("set symbol-filename on" is a partial -solution). +-- -investigate "x/s 0" (right now stops early) (I think maybe GDB is -using a 0 address for bad purposes internally). - -Make "info path" and path_command work again (but independent of the -environment either of gdb or that we'll pass to the inferior). + Code Cleanups: General + ====================== -Make GDB understand the GCC feature for putting octal constants in -enums. Make it so overflow on an enum constant does not error_type -the whole type. Allow arbitrarily large enums with type attributes. -Put all this stuff in the testsuite. +The following are more general cleanups and fixes. They are not tied +to any specific release. -Make TYPE_CODE_ERROR with a non-zero TYPE_LENGTH more useful (print -the value in hex; process type attributes). Add this to the -testsuite. This way future compilers can add new types and old -versions of GDB can do something halfway reasonable. -Clean up formatting of "info registers" on MIPS and 88k. See if it -is possible to do this generically across all target architectures. + New Features and Fixes + ====================== -GDB gets bfd/corefile.c and gdb/corefile.c confused (this should be easy to -repeat even with something more recent than GDB 4.9). +These are harder than cleanups but easier than work involving +fundamental architectural change. -Check that unmatched RBRAC doesn't abort(). +-- -Fix mdebugread.c:parse_type to do fundamental types right (see -rs6000_builtin_type in stabsread.c for what "right" is--the point is -that the debug format fixes the sizes of these things and it shouldn't -depend on stuff like TARGET_PTR_BIT and so on. For mdebug, there seem -to be separate bt* codes for 64 bit and 32 bit things, and GDB should -be aware of that). Also use a switch statement for clarity and speed. + Language Support + ================ -Investigate adding symbols in target_load--some targets do, some -don't. +New languages come onto the scene all the time. -Put dirname in psymtabs and change lookup*symtab to use dirname (so -/foo/bar.c works whether compiled by cc /foo/bar.c, or cd /foo; cc -bar.c). +-- -Merge xcoffread.c and coffread.c. Use breakpoint_re_set instead of -fixup_breakpoints. +Re: Various C++ things -Fix byte order and int size sins in tm-a29k.h -(EXTRACT_RETURN_VALUE). Perhaps should reproduce bug and verify fix -(or perhaps should just fix it...). +value_headof/value_from_vtable_info are worthless, and should be +removed. The one place in printcmd.c that uses it should use the RTTI +functions. -Make a watchpoint on a constant expression an error (or warning -perhaps) +RTTI for g++ should be using the typeinfo functions rather than the +vtables. The typeinfo functions are always at offset 4 from the +beginning of the vtable, and are always right. The vtables will have +weird names like E::VB sometimes. The typeinfo function will always +be "E type_info function", or somesuch. -Make a watchpoint which contains a function call an error (it is -broken now, making it work is probably not worth the effort). +value_virtual_fn_field needs to be fixed so there are no failures for +virtual functions for C++ using g++. -Re-do calls to signal() in remote.c, and inflow.c (set_sigint_trap and -so on) to be independent of the debugging target, using target_stop to -stop the inferior. Probably the part which is now handled by -interrupt_query in remote.c can be done without any new features in -the debugging target. +Testsuite cases are the major priority right now for C++ support, +since i have to make a lot of changes that could potentially break +each other. -New test case based on weird.exp but in which type numbers are not -renumbered (thus multiply defining a type). This currently causes an -infinite loop on "p v_comb". +-- -Nuke baseclass_addr. -Nuke USG define. + Symbol Support + ============== -"source file more recent" loses on re-read +-- -Fix 386 floating point so that floating point registers are real -registers (but code can deal at run-time if they are missing, like -mips and 68k). This would clean up "info float" and related stuff. +Investiagate ways of reducing memory. -Look at Solaris bug in interrupt.exp. Can get out of syscall with -PRSABORT (syscall will return EINTR) but merely doing that leads to a -"can't read memory" error. +-- -gcc -g -c enummask.c then gdb enummask.o, then "p v". GDB complains -about not being able to access memory location 0. +Investigate ways of improving load time. --------------------- enummask.c -enum mask -{ - ANIMAL = 0, - VEGETABLE = 1, - MINERAL = 2, - BASIC_CATEGORY = 3, +-- - WHITE = 0, - BLUE = 4, - GREEN = 8, - BLACK = 0xc, - COLOR = 0xc, + Testsuite Support + ================= - ALIVE = 0x10, +There are never to many testcases. - LARGE = 0x20 -} v; +-- -If try to modify value in file with "set write off" should give -appropriate error not "cannot access memory at address 0x65e0". +Better thread testsuite. -Why do we allow a target to omit standard register names (NO_STD_REGS -in tm-z8k.h)? I thought the standard register names were supposed to -be just that, standard. +-- -Make DEBUG_EXPRESSIONS a maintenance command, dependent on -MAINTENANCE_COMMANDS. +Better C++ testsuite. -Allow core file without exec file on RS/6000. +-- -Make sure "shell" with no arguments works right on DOS. + Architectural Changes: General + ============================== -Make gdb.ini (as well as .gdbinit) be checked on all platforms, so -the same directory can be NFS-mounted on unix or DOS, and work the -same way. +These are harder than simple cleanups / fixes and, consequently +involve more work. Typically an Architectural Change will be broken +down into a more digestible set of cleanups and fixes. -cd ~/tmp/<M-?> causes infinite loop (where ~/tmp is a directory). +-- -Get SECT_OFF_TEXT stuff out of objfile_relocate (might be needed to -get RS/6000 to work right, might not be immediately relevant). + Architectural Change: Multi-arch et al. + ======================================= -Clean up add_toc_to_loadinfo +The long term objective is to remove all assumptions that there is a +single target with a single address space with a single instruction +set architecture and single application binary interface. -Think about attached processes and sharing terminal. +This is an ongoing effort. The first milestone is to enable +``multi-arch'' where by all architectural decisions are made at +runtime. -John sez in reference to ignoring errors from tcsegpgrp if attach_flag: -set_tty_state should not have any trouble with attached processes. -Instead, the tty handling should leave the pgrp of the tty alone when -attaching to processes (perhaps pass terminal_init_inferior a flag -saying whether we're attaching). +It should be noted that ``gdbarch'' is really ``gdbabi'' and +``gdbisa''. Once things are multi-arched breaking that down correctly +will become much easier. -PAGE_SIZE redefined warnings on AIX. Probably should be using -BFD_PAGE_SIZE throughout BFD. +-- -Rewrite proceed, wait_for_inferior, and normal_stop to clean them up. -Suggestions: + Architectural Change: MI, LIBGDB and scripting languages + ======================================================== - 1) Make each test in wait_for_inferior a seperate subroutine - call. - 2) Combine wait_for_inferior and normal_stop to clean up - communication via global variables. - 3) See if you can find some way to clean up the global - variables that are used; possibly group them by data flow - and information content? +See also architectural changes related to the event loop. LIBGDB +can't be finished until there is a generic event loop being used by +all targets. -Work out some kind of way to allow running the inferior to be done as -a sub-execution of, eg. breakpoint command lists. Currently running -the inferior interupts any command list execution. This would require -some rewriting of wait_for_inferior & friends, and hence should -probably be done in concert with the above. +The long term objective is it to be possible to integrate GDB into +scripting languages. -Add function arguments to gdb user defined functions. +-- -Add convenience variables that refer to exec file, symbol file, -selected frame source file, selected frame function, selected frame -line number, etc. + Architectural Change: Async + =========================== -Add a "suspend" subcommand of the "continue" command to suspend gdb -while continuing execution of the subprocess. Useful when you are -debugging servers and you want to dodge out and initiate a connection -to a server running under gdb. +While GDB uses an event loop when prompting the user for input. That +event loop is not exploited by targets when they allow the target +program to continue. Typically targets still block in (target_wait()) +until the program again halts. -Add stab information to allow reasonable debugging of inline functions -(possibly they should show up on a stack backtrace? With a note -indicating that they weren't "real"?). +The closest a target comes to supporting full asynchronous mode are +the remote targets ``async'' and ``extended-async''. -Modify the naked "until" command to step until past the current source -line, rather than past the current pc value. This is tricky simply -because the low level routines have no way of specifying a multi-line -step range, and there is no way of saying "don't print stuff when we -stop" from above (otherwise could just call step many times). - -Modify the handling of symbols grouped through BINCL/EINCL stabs to -allocate a partial symtab for each BINCL/EINCL grouping. This will -seriously decrease the size of inter-psymtab dependencies and hence -lessen the amount that needs to be read in when a new source file is -accessed. - -Do an "x/i $pc" after each stepi or nexti. - -Modify all of the disassemblers to use printf_filtered to get correct -more filtering. - -Modify gdb to work correctly with Pascal. - -Add a command for searching memory, a la adb. It specifies size, -mask, value, start address. ADB searches until it finds it or hits -an error (or is interrupted). +-- # Local Variables: # mode: text |
