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Diffstat (limited to 'gdb/TODO')
| -rw-r--r-- | gdb/TODO | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/gdb/TODO b/gdb/TODO new file mode 100644 index 00000000000..fcbcd16bea6 --- /dev/null +++ b/gdb/TODO @@ -0,0 +1,471 @@ +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. + +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. + +Add an "info bfd" command that displays supported object formats, +similarly to objdump -i. + +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. + +Make single_step() insert and remove breakpoints in one operation. + +Speed up single stepping by avoiding extraneous ptrace calls. + +Speed up single stepping by not inserting and removing breakpoints +each time the inferior starts and stops. + +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. + +Update gdbint.texinfo to include doc on the directory structure and +the various tricks of building gdb. + +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. + +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. + +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. + +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. + +Finish the C++ exception handling stub routines. Lint points them out +as unused statics functions. + +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). + +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. + +"help address" ought to find the "help set print address" entry. + +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 prompt at end of screen should accept space as well as CR. + +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! + +vtblprint of a vtbl should demangle the names it's printing. + +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, ...)". + +"i program" should work for core files, and display more info, like what +actually caused it to die. + +"x/10i" should shorten the long name, if any, on subsequent lines. + +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. + +"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. + +terminal_ours versus terminal_inferior: cache state. Switch should be a noop +if the state is the same, too. + +ptype $i6 = void??! + +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.) + +help completion, help history should work. + +Check that we can handle stack trace through varargs AND alloca in same +function, on 29K. + +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. + +There should be a way for "set" commands to validate the new setting +before it takes effect. + +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. + +"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. + +inferior_status should include stop_print_frame. It won't need to be +reset in wait_for_inferior after bpstat_stop_status call, then. + +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. + +Make "target xxx" command interruptible. + +Handle add_file with separate text, data, and bss addresses. Maybe +handle separate addresses for each segment in the object file? + +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. + +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). + +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. + +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... + +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. + +Sort help and info output. + +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. + +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). + +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. + +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). + +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 + +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. + +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. + +SunOS should have a target_lookup_symbol() for common'd things allocated +by the shared library linker ld.so. + +When listing source lines, check for a preceding \n, to verify that +the file hasn't changed out from under us. + +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. + +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). + +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. + +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. + +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). + +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. + +Investigate adding symbols in target_load--some targets do, some +don't. + +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. + +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...). + +Make a watchpoint on a constant expression an error (or warning +perhaps) + +Make a watchpoint which contains a function call an error (it is +broken now, making it work is probably not worth the effort). + +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. + +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. + +"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. + +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. + +-------------------- enummask.c +enum mask +{ + ANIMAL = 0, + VEGETABLE = 1, + MINERAL = 2, + BASIC_CATEGORY = 3, + + WHITE = 0, + BLUE = 4, + GREEN = 8, + BLACK = 0xc, + COLOR = 0xc, + + ALIVE = 0x10, + + 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". + +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. + +Allow core file without exec file on RS/6000. + +Make sure "shell" with no arguments works right on DOS. + +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. + +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). + +Clean up add_toc_to_loadinfo + +Think about attached processes and sharing terminal. + +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). + +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: + + 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? + +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. + +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. + +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. + +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"?). + +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 +# End: |