- Gpc - gnu.de

Re: [Core] [RFA/DWARF2] Handle nested subprograms in CU pc bound calculation
by Jonas Maebe 01 Oct '08

01 Oct '08

On 01 Oct 2008, at 18:39, Joel Brobecker wrote: > The answer to the question above lies in the Pascal parser. But when > there are homonyms, how do you specify in your program exactly which > one you mean? unitname.functionname > And does GDB provide the same method for distinguishing > these homonyms? I don't think so. The main problem is that there is no common way of mangling procedure/function names in Pascal. FPC and GPC mangle them in different ways, and as far as I know gdb has no support to demangle either (it definitely does not support demangling FPC names). For this reason, I always use either symbol names or sourcefile:linenr to place breakpoints. Jonas

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Re: [RFA/DWARF2] Handle nested subprograms in CU pc bound calculation
by Pierre Muller 01 Oct '08

01 Oct '08

> -----Message d'origine----- > De : Joel Brobecker [mailto:brobecker@adacore.com] > Envoyé : Wednesday, October 01, 2008 3:16 AM > À : Pierre Muller; gdb-patches(a)sourceware.org > Objet : Re: [RFA/DWARF2] Handle nested subprograms in CU pc bound > calculation > > > > Actually, now that I think of it, a slightly cleaner approach would > > > probably be to extend the language vector to add a flag set to > > > non-zero for the languages that want nested-subprogram handling. > > > The only slight issue is that the CU references the language enum, > > > which means we need to go from that enum to the language_defn to > get access to the flag. > > > > I think you should stick with a language test in the DWARF reader. > > OK. Would the following kind of patch be what you have in mind? > Or would you prefer that the function simply take a language, rather > than a CU. Or actually no function at all? > > 2008-09-30 Joel Brobecker <brobecker(a)adacore.com> > > * dwarf2read.c (dwarf2_handle_nested_subprograms_p): New > function. > (add_partial_subprogram): Replace check of Ada language by call > to dwarf2_handle_nested_subprograms_p. > (dwarf2_get_subprogram_pc_bounds, load_partial_dies): Likewise. This looks fine for me! > This is only just for comments, as there is still one question open: > For Ada, we store the symbols for nested subprograms in the global > context. This allows us to break on these functions even when these > functions are not defined in the current context. Do we want to do the > same with Pascal? Right now, I left this functionality out... > In Ada, we have found it to be extremely convenient to not have to be > inside the enclosing function before we can insert the breakpoint. > When there are ambiguities (say two functions have a nested subprogram > with the same name), the ambiguity can be resolved using the fully > qualified name. I believe that, at least with the Free Pascal compiler and stabs debugging format (which is the format I worked on), all nested subprograms where also in the global context and thus I would not mind to do the same for pascal language. I must confess that I stopped working for the Free Pascal compiler more or less when the dwarf debugging format was added, and I almost don't know anything about that format... The only thing that I can tell, is that last time I checked Free Pascal (version 2.2.0 windows 32bit target) with -gw (dwarf debugging format) I still got lots of errors while trying to load the compiler inside gdb :( I know even less about GNU pascal compiler, but as this compiler is base on the GNU multi-language compiler, I would except it to behave closer to GNU C++ or GNU Ada. I must confess that I don't even know if the full specification would work for pascal in case the same name is used globally and as a nested procedure (I do know that you are allowed to reuse a name defined globally as a local procedure, function or variable inside a function, but I don't know if the (gdb) break GlobalFuntion.LocalFunction would work) Feedback from both Free Pascal and GNU pascal developers would be useful here and more generally on pascal dwarf support. > Tested on x86-linux, no regression (but I don't have a Pascal > compiler). The pascal testsuite is ridiculously tiny (I only wrote a few very basic tests) and there is nothing about nested functions/procedures in it. So there is nothing to expect on this side. By the way, it would probably be useful to repeat the tests with different debugging formats. How can this be done in your testsuite directory? Pierre Muller Pascal language support maintainer for GDB

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OpenBSD build
by G. Ramalho 15 Sep '08

15 Sep '08

Hello, I'm trying to build GPC on my OpenBSD box. xgcc seems to be correctly built but I can't get past the following: CC="`echo /root/gpc-build/gcc/xgcc -B/root/gpc-build/gcc/ -B/usr/local/i386-unknown-openbsd4.3/bin/ -B/usr/local/i386-unknown-openbsd4.3/lib/ -isystem /usr/local/i386-unknown-openbsd4.3/include' ' | sed -e 's,$-[BI]$$[^/][^:]$,\1../../\2,g;s,^$[^/][^:]*/$,../../\1,'`" PC="`echo ./xgpc -B./' ' | sed -e 's,$-[BI]$$[^/][^:]$,\1../../\2,g;s,^$[^/][^:]*/$,../../\1,'`" CONFIG_SITE=nonexisting-file \ $src/p/rts/configure --silent > /dev/null --srcdir=$src/p/rts \ `if [ x@with_shared@ = xyes ]; then echo '--with-shared'; fi` configure: error: installation or configuration problem: C compiler cannot create executables. gmake[1]: *** [p/rts/Makefile] Error 1 gmake[1]: Leaving directory `/root/gpc-build/gcc' gmake: *** [all-gcc] Error 2 OS: OpenBSD 4.3 / i386 (VMWare). GCC/GPC : 3.3.5 / 20060325 Any help is really appreciated. Ramalho.

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Garbage Collection
by Prof. Harley Flanders 03 Sep '08

03 Sep '08

A question for the GPC list: Suppose I have defined type Vec = array[1..1000] of Extended; // 10,000 bytes var A, B, C, D: Vec; function Sum(const A, B: Vec): Vec; In the assignment D := Sum(Sum(A, B), C); there is an intermediate result Sum(A, B), going to an unnamed temporary vector. Does garbage collection pick up that space? Similar question with operator + (const A, B: Vec) C: Vec; D := (A+B)+C; More complicated: Delphi mode, so I have "Result" available var Zero: Vec; // Zero[J] = 0 for all J function Foo(A: Vec; N: Word): Vec; var B: Vec; begin if N = 0 then Result := Zero else if Odd(N) then Result := A + Foo(A, N - 1) else begin B := (Foo(A, N div 2) Result := B + B; end; end; // Foo Garbage collection handles this correctly? Whatever the answers, how do I PROVE them by measuring stack, heap, or whatever? Thanks, HF -- ============================= Prof. Harley Flanders 3533 Windemere Court Ann Arbor, MI 48105-2867 Home: 734 668 1546 harley(a)umich.edu =============================

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Console apps
by Prof. Harley Flanders 02 Sep '08

02 Sep '08

Would anyone please tell me what to write in a Console App so DOS opens in Full Screen mode, not in a window, and in 80 x 25 mode (80 columns, 25 lines). Thank you, HF -- ============================= Prof. Harley Flanders 3533 Windemere Court Ann Arbor, MI 48105-2867 Home: 734 668 1546 harley(a)umich.edu =============================

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GNU Pascal based TeX
by Wolfgang Helbig 07 Jul '08

07 Jul '08

Hi, at http://www.ba-stuttgart.de/~helbig/tex-gpc/ you'll find a set of change files to build GNU Pascal based TeX, METAFONT, weave, tangle and some other related programs. Especially the file tex.ch contains lots of examples how to use GPC extensions. Enjoy, Wolfgang

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Re: turn off lazyIO on disk files
by Wolfgang Helbig 04 Jul '08

04 Jul '08

Hi, Frank Heckenbach wrote: >> On writing, GPC doesn't buffer yet at all; it's not implemented yet. >> It's not that it couldn't be done, but it's more tricky, because GPC >> supports various ways of seeking, pre-reading, getting the file >> position etc., which all would have to take account of the buffers. >> >> If it's a serious problem you could kludge it by installing a >> user-defined file write routine which can do the buffering. If you >> know that your application only does sequential writes, this would >> work. I've done this once (see RewriteBuffer in cgi.pas in >> http://fjf.gnu.de/misc/cgiprogs.tar.bz2) Let me know if you need >> more details. >> >> Frank >> Thanks for the enlightement about buffering in GPC. And Emil Jerabek wrote: >The bottleneck in TeX's I/O is the output to the dvi file, which is >done byte by byte (there's no other choice in standard Pascal). Knuth >himself notes that this is inefficient, the porter is expected to >optimize it: >In the case of GPC, it is trivial to replace the write_dvi procedure >with a single call to BlockWrite. This makes a huge difference in the >running time. Did that. And the time command shows the difference: 64.45 real 15.16 user 48.45 sys 11.40 real 10.55 user 0.57 sys Compares pretty good to a web2c based distribution of TeX, in this case teTeX-3.0: 7.54 real 7.01 user 0.17 sys Thanks to both of you, Wolfgang Helbig -- "Dijkstra is right, but you don't say such things!" (A less courageous programmer)

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turn off lazyIO on disk files
by Wolfgang Helbig 04 Jul '08

04 Jul '08

Hi, the program, Don Knuth's TeX adapted to GPC version 2.1, does heavy I/O on text files. I noticed a very high percentage of system time. I believe this is due to lazy I/O, which seems to be unbuffered. GPC should apply lazy/IO when the text file comes from the keyboard, but to use buffered I/O when it comes from the disk. Is there a way to turn off lazy/IO on nonterminal text files? Greetings, Wolfgang Helbig

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Indent program for the GPC
by pripoae teodor anton 04 Jul '08

04 Jul '08

Hello. I read in the to-do list than a planned feature is a indent-like source code formatter for Pascal. I have three questions: 1. Is anybody who is doing this job? I saw something like this here: http://www.gnu-pascal.de/crystal/gpc/en/mail4247.html?pos=13294915#13294915 but it seems to be unfinished, and it seems to be very long time ago (in 2000). 2. What are the multi-styles for this (in the c indent program called indent, I know that there are a lot of styles: k&r, gnu, berkeleyetc...) 3. How can i contribute to GPC? I haven't tryed to contribute to GNU software yet. I wrote a pascal indent (with some modes, (unix/dos) and with output file), but it has only one mode (yet). Regards, Pripoae Teodor Anton, pripoae_teodor_anton(a)yahoo.com

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GPC and the Linux Standard Base
by Yang Lao 12 Jun '08

12 Jun '08

I wonder if any version of gpc for linux is compliant or conformant with the Linux Standard Base. When I run your hello program through their lsbappchk it gives messages like this: FAIL Symbol isnanl is used, but is not included in LSB 3.2 (Core & C++ & Desktop)

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