Joel E. Denny [Mon, 4 Jan 2010 19:13:43 +0000 (14:13 -0500)]
Fix some comments concerning LR(0) versus LALR(1).
Stop equating LR(0) with nondeterminism and LALR(1) with
determinism. That is, if all states are consistent, then LR(0)
tables are deterministic. On the other hand, LALR(1) tables
might be nondeterministic before conflict resolution, and GLR
permits LALR(1) tables to remain nondeterministic.
* src/LR0.c, src/LR0.h: Here.
* src/lalr.c, src/lalr.h: Here.
* src/main.c (main): Here.
* src/state.c, src/state.h: Here.
Joel E. Denny [Wed, 30 Dec 2009 08:20:11 +0000 (03:20 -0500)]
POSIX: warn if %prec's token was not defined.
Reported by Florian Krohm at
<http://lists.gnu.org/archive/html/bug-bison/2009-12/msg00005.html>.
* NEWS (2.4.2): Document.
* src/reader.c (grammar_rule_check): Implement.
(grammar_current_rule_prec_set): Add comments explaining that we
here assume a %prec identifier is a token, but we still manage
to support POSIX.
* tests/input.at (%prec's token must be defined): New test
group.
(cherry picked from commit f1ceed07743630aa2aef7c77d8bde23c3794ee1b)
Joel E. Denny [Tue, 29 Dec 2009 17:43:26 +0000 (12:43 -0500)]
portability: `<' and `>' are not always defined on addresses.
Specifically, don't sort objects by their memory addresses when
they're not allocated in the same array or other object. Though
I haven't found a test case where that fails on my platform, C
says the behavior is undefined.
* src/AnnotationList.c (AnnotationList__insertInto): Remove
FIXME. Use new id field of InadequacyList nodes rather than
their memory addresses when sorting.
(AnnotationList__compute_from_inadequacies): Add
inadequacy_list_node_count argument to pass to
InadequacyList__new_conflict.
* src/AnnotationList.h
(AnnotationList__compute_from_inadequacies): Update prototype
and documentation for new argument.
* src/InadequacyList.c (InadequacyList__new_conflict): Add
node_count argument and use it to assign a unique ID.
* src/InadequacyList.h (InadequacyListNodeCount): New typedef.
(InadequacyList): Add id field.
(InadequacyList__new_conflict): Update prototype and
documentation for new argument.
* src/ielr.c (ielr_compute_annotation_lists): Update
AnnotationList__compute_from_inadequacies invocation.
(cherry picked from commit 2728ac7ecd663c4a60f94fe7ab7679a9e83ebcd0)
Joel E. Denny [Sun, 20 Dec 2009 07:22:53 +0000 (02:22 -0500)]
Fix handling of yychar manipulation in user semantic actions.
The problem was that yacc.c didn't always update the yychar
translation afterwards. However, other skeletons appear to be
fine. glr.c appears to already translate yychar before every
use. lalr1.cc does not define yychar and does not document its
replacement, yyla, for users. It does provide yyclearin, but
that does not manipulate yyla and thus requires no translation
update. In lalr1.java, yychar is out of scope during semantic
actions.
* NEWS (2.5): Document.
* data/yacc.c (YYBACKUP): Don't bother translating yychar into
yytoken here.
(yyparse, yypush_parse): Instead, translate before every use of
yytoken, and add comments explaining this approach.
* tests/actions.at (Destroying lookahead assigned by semantic
action): New test group checking that translation happens before
lookahead destructor calls at parser return. Previously,
incorrect destructors were called.
* tests/conflicts.at (parse.error=verbose and consistent
errors): New test group checking that translation happens at
syntax error detection before the associated verbose error
message and the associated lookahead destructor calls. While
the destructor call is fixed by this patch, the verbose error
message is currently incorrect due to another bug (see
comments in test group), so this is an expected failure for now.
Joel E. Denny [Mon, 21 Dec 2009 19:58:48 +0000 (14:58 -0500)]
YYFAIL: warn about uses and remove from lalr1.java.
* NEWS (2.5): Document.
* data/lalr1.java (parser::YYStack::YYFAIL): Rename to YYERRLAB,
and make it private. Update all uses.
* src/scan-code.l (SC_RULE_ACTION): Implement warning.
Joel E. Denny [Wed, 16 Dec 2009 18:19:19 +0000 (13:19 -0500)]
Add gcc's -Wundef to test suite and fix another warning from it.
* NEWS (2.4.2): Update description of -Wundef fix.
* configure.ac (WARN_CXXFLAGS_TEST): New substitution.
(WARN_CFLAGS_TEST): New substitution.
* data/glr.c: Avoid warning about __STRICT_ANSI__.
* tests/atlocal.in (CFLAGS): Use WARN_CFLAGS_TEST instead of
WARN_CFLAGS.
(NO_WERROR_CFLAGS): Likewise.
(CXXFLAGS): Use WARN_CXXFLAGS_TEST instead of WARN_CXXFLAGS.
Jonathan Nieder [Wed, 16 Dec 2009 04:07:46 +0000 (22:07 -0600)]
Simplify y.tab.c when location tracking is disabled.
* data/yacc.c: Do not check YYLTYPE_IS_TRIVIAL if location
tracking is not enabled. Instead, unconditionally define
YY_LOCATION_PRINT as a no-op for backward compatibility.
Joel E. Denny [Tue, 15 Dec 2009 05:15:41 +0000 (00:15 -0500)]
portability: use -DGNULIB_POSIXCHECK.
Reported by Eric Blake. See discussions at
<http://lists.gnu.org/archive/html/bug-bison/2009-09/msg00008.html>
and
<http://lists.gnu.org/archive/html/bug-gnulib/2009-10/msg00108.html>.
* HACKING (Release checks): Suggest -DGNULIB_POSIXCHECK.
* bootstrap.conf (gnulib_modules): Add all the printf modules
suggested by -DGNULIB_POSIXCHECK. Add realloc-posix as
suggested by -DGNULIB_POSIXCHECK for gnulib's own vasnprintf.c.
(excluded_files): Remove m4/printf-posix.m4.
* tests/atlocal.in (LIBS): As for LDADD in src/local.mk, add
lib/libbison.a so gnulib libraries can be linked.
Joel E. Denny [Tue, 15 Dec 2009 22:20:31 +0000 (17:20 -0500)]
gnulib: update for fix of fprintf-posix, which we'll use soon.
* etc/prefix-gnulib-mk (prefix): Adjust regex for make file
targets so that gnulib's new arg-nonnull.h and link-warning.h
are matched.
* gnulib: Update.
Joel E. Denny [Mon, 14 Dec 2009 21:04:00 +0000 (16:04 -0500)]
Expand GLR acronym in summary of Bison.
Based on discussion with Akim Demaille starting at
<http://lists.gnu.org/archive/html/bison-patches/2009-04/msg00087.html>.
* doc/bison.texinfo (Introduction): Here.
* src/getargs.c (usage): Here.
(cherry picked from commit 51c7ca01e2c9cfb5c7a274bed0e14899adbd005c)
Joel E. Denny [Fri, 16 Oct 2009 23:27:12 +0000 (19:27 -0400)]
cleanup.
* src/Sbitset.c (Sbitset__new_on_obstack): Use Sbitset instead
of char*.
(Sbitset__isEmpty): Use Sbitset instead of char*.
* src/Sbitset.h (Sbitset): Make it a pointer to unsigned char
instead of char. This helps to avoid casting errors.
(Sbitset__or): Use Sbitset instead of char*.
Joel E. Denny [Fri, 16 Oct 2009 23:20:43 +0000 (19:20 -0400)]
portability: don't assume 8-bit bytes.
That is, use CHAR_BIT and UCHAR_MAX instead of 8 and 0xff.
* src/Sbitset.h (Sbitset__nbytes): Here.
(Sbitset__byteAddress): Here.
(Sbitset__bit_mask): Here.
(Sbitset__last_byte_mask): Here.
(Sbitset__ones): Here.
(SBITSET__FOR_EACH): Here.
Joel E. Denny [Mon, 5 Oct 2009 03:44:44 +0000 (23:44 -0400)]
Minor code cleanup.
* src/parse-gram.y: Clean up sorting of declarations.
Use types to simplify %printer declarations where possible.
Provide %printer for BRACKETED_ID and symbol.prec.
* src/symtab.c: Whitespace change.
Joel E. Denny [Mon, 5 Oct 2009 02:59:18 +0000 (22:59 -0400)]
tests: skip tests of file names that platform does not support.
Reported by Michael Raskin at
<http://lists.gnu.org/archive/html/bug-bison/2009-09/msg00001.html>.
* THANKS (Michael Raskin): Add.
* tests/output.at (AT_CHECK_OUTPUT_FILE_NAME): Fix. Cygwin used
to fail at least for file names containing ":" or "\".
(cherry picked from commit 2ceb8c617cac934b45f101ab44508d72239c894b)
Except when memory reallocation is required, this change
eliminates the need to invoke yysyntax_error twice and thus to
repeat the collection of lookaheads. It also prepares for
future extensions that will make those repetitions more
expensive and that will require additional memory management in
yysyntax_error. Finally, it fixes an obscure bug already
exercised in the test suite.
* data/yacc.c (yysyntax_error): Add arguments for message
buffer variables stored in the parser. Instead of size, return
status similar to yyparse status but indicating success of
message creation. Other than the actual reallocation of the
message buffer, import and clean up memory management code
from...
(yyparse, yypush_parse): ... here.
* tests/regression.at (parse.error=verbose overflow): No longer
an expected failure.
Joel E. Denny [Wed, 23 Sep 2009 21:37:58 +0000 (17:37 -0400)]
yysyntax_error: test memory management more.
* tests/atlocal.in (NO_WERROR_CFLAGS): New cpp macro.
* tests/regression.at (parse.error=verbose and
YYSTACK_USE_ALLOCA): New test group.
(parse.error=verbose overflow): New test group that reveals an
obscure bug. Expected fail for now.
Joel E. Denny [Sun, 4 Oct 2009 18:33:28 +0000 (14:33 -0400)]
benchmarks: use %debug consistently among grammars.
* etc/bench.pl.in (generate_grammar_triangular): Do not activate
%debug by default. It can affect the timings even if yydebug=0.
(generate_grammar_calc): For consistency with other grammars,
use YYDEBUG environment variable to set yydebug.
Joel E. Denny [Tue, 29 Sep 2009 10:54:38 +0000 (06:54 -0400)]
Use the correct conversion specifier for size_t.
Reported by Jim Meyering.
* src/Sbitset.h (SBITSET__INDEX__CONVERSION_SPEC): New, "zu"
because Sbitset__Index is size_t.
* src/Sbitset.c (Sbitset__fprint): Use it instead of %d.
Alex Rozenman [Sat, 19 Sep 2009 09:59:33 +0000 (12:59 +0300)]
Keep sub-messages aligned. Fix strings for translation.
* src/location.h: (location_print): Add return value.
* src/location.c: (location_print): Return number of printed
characters.
* src/complain.h: Two new functions (complain_at_indent,
warn_at_indent).
* src/complain.cpp: Implement the alignment mechanism. Add new
static variable (indent_ptr). Use and update it (error_message,
complain_at_indent, warn_at_indent).
* src/scan-code.l: Fix strings for translations. Use new *_indent
functions (parse_ref, show_sub_messages).
* NEWS (2.5): Add an announcement about named references.
* doc/bison.texinfo (Decl Summary): Document the "lex_symbol" and
"variant" %define variables.
(C++ Semantic Values): Split into...
(C++ Unions, C++ Variants): these.
The latter is new.
(C++ Parser Interface): Fix type names.
Document parser::syntax_error.
Document the fact that locations are not mandatory.
(C++ Scanner Interface): Split into...
(Split Symbols, Complete Symbols): these.
The later is new.
(Calc++ Parsing Driver): Use variants.
Add more comments.
Adjust style.
(Calc++ Parser): Declare all the tokens, no
longer accept raw characters.
Remove %union.
Adjust types and printers.
Remove destructors.
(Calc++ Scanner): Use make_<SYMBOL> functions.
Use strerror in error message.
lalr1.cc: factor the yytranslate_ invocation in make_SYMBOLS.
* data/c++.m4, data/lalr1.cc (parser::symbol_type): Change the
constructor to take a token_type instead of the (internal) symbol
number.
Call yytranslate_.
* data/variant.hh (b4_symbol_constructor_define_): Therefore,
don't call yytranslate_ here.
Joel E. Denny [Sun, 6 Sep 2009 20:59:04 +0000 (16:59 -0400)]
Clean up yacc.c a little.
* data/yacc.c: Clean up M4 for readability, and make output
whitespace more consistent. For the main parse function
comment, instead of saying "yyparse or yypush_parse", say either
"yyparse" or "yypush_parse" depending on which it actually is.
It is common to use sort of factories in the user actions. These
factories may check some "syntactic" constraints that are not
enforced by the grammar itself. This is possible using YYERROR
within the action itself. Provide the user with a means to throw
a syntax_error exception.
* data/c++.m4 (b4_public_types_declare, b4_public_types_define):
Declare and define yy::parser::syntax_error.
* data/lalr1.cc: Include stdexcept.
(yy::parser::parse): Wrap the user action within a try/catch.
* data/glr.cc: Include stdexcept.
* NEWS (2.6): Document %param, %lex-param, and %parse-param
changes.
* doc/bison.texinfo: Document that %lex-param and %parse-param
are n-ary.
Changes some examples to demonstrate it.
(Calc++ Parser): Use %param.
Provide a means to factor lex-param and parse-param common
declarations.
* src/parse-gram.y (param_type): New.
Define a %printer for it.
(add_param): Use it.
(%parse-param, %lex-param): Merge into...
(%parse): this new token.
Adjust the grammar to use it.
* src/scan-gram.l (RETURN_VALUE): New.
(RETURN_PERCENT_FLAG): Use it.
(RETURN_PERCENT_PARAM): New.
Use it to support %parse-param, %lex-param and %param.
Joel E. Denny [Thu, 3 Sep 2009 17:59:07 +0000 (13:59 -0400)]
Use aver not assert.
* src/output.c: Don't include assert.h.
(output_skeleton): Use aver not assert.
* src/system.h (aver): In documentation of why, add links to
Paul Eggert's explanations in the mailing lists.
Alex Rozenman [Sat, 5 Sep 2009 10:16:45 +0000 (13:16 +0300)]
Use "Unresolved reference" error message when no symbols were found
in a symbolic reference resolution. Remove .expr and -expr from
the shown reference when the reference is unresolved.
* src/scan-code.l: Change the error message, adjust location columns,
rename variable "exact_mode" to "explicit_bracketing".
* tests/named-ref.at: Adjust existing tests and add a new one.
Joel E. Denny [Thu, 3 Sep 2009 18:27:16 +0000 (14:27 -0400)]
Don't suppress warnings about unused parse.error.
* data/bison.m4 (b4_error_verbose_flag): Don't examine value of
%define variable parse.error unless b4_error_verbose_flag is
actually expanded in a skeleton.
Joel E. Denny [Sat, 29 Aug 2009 20:25:58 +0000 (16:25 -0400)]
Fix gcc 3.4.4 shadowing warning reported by Eric Blake.
See
<http://lists.gnu.org/archive/html/bison-patches/2009-08/msg00093.html>.
* src/scan-code.h (code_props_rule_action_init): Rename
named_ref arg to name so it doesn't shadow named_ref type. This
makes it consistent with the function definition in scan-code.l
anyway.
Joel E. Denny [Thu, 27 Aug 2009 07:52:53 +0000 (03:52 -0400)]
tests: use perl for printing special sequences to files.
And skip tests if perl is not available. This is better than
playing tricks with shell portability. Suggested by Akim
Demaille.
* tests/input.at (Bad character literals): Use it here for
omitting final newlines.
(Bad escapes in literals): Use it here for special characters.
Joel E. Denny [Wed, 26 Aug 2009 06:40:38 +0000 (02:40 -0400)]
Actually handle the yytable zero value correctly this time.
* data/bison.m4 (b4_integral_parser_tables_map): Don't mention
zero values in the YYTABLE comments.
* data/glr.c (yytable_value_is_error): Don't check for zero
value.
* data/lalr1.cc (yy_table_value_is_error_): Likewise.
* data/yacc.c (yytable_value_is_error): Likewise.
* data/lalr1.java (yy_table_value_is_error_): Likewise.
(yysyntax_error): Fix typo in code: use yytable_ not yycheck_.
* src/tables.h: In header comments, explain why it's useless to
check for a zero value in yytable.
Joel E. Denny [Tue, 25 Aug 2009 23:41:49 +0000 (19:41 -0400)]
More fixes related to last two patches.
* data/bison.m4 (b4_integral_parser_tables_map): Fix YYTABLE
comments: zero indicates syntax error not default action.
* data/c.m4 (b4_table_value_equals): Comment that YYID must be
defined.
* data/glr.c (yyis_pact_ninf): Rename to...
(yypact_value_is_default): ... this.
(yyisDefaultedState): Update for rename.
(yyis_table_ninf): Rename to...
(yytable_value_is_error): ... this, and check for value zero
besides just YYTABLE_NINF.
(yygetLRActions): Check for default value from yypact. It
appears that this check is always performed before this function
is invoked, and so adding the check here is probably redundant.
However, the code may evolve after this subtlety is forgotten.
Also, update for rename to yytable_value_is_error. Because that
macro now checks for zero, a different but equivalent branch of
the if-then-else here is evaluated.
(yyreportSyntaxError): Update for rename to
yytable_value_is_error. The zero condition was mishandled
before.
(yyrecoverSyntaxError): Update for renames. No behavioral
changes.
* data/lalr1.cc, data/lalr1.java (yy_pact_value_is_default_):
New function.
(yy_table_value_is_error_): New function.
(parse): Use new functions where possible. No behavioral
changes.
(yysyntax_error_, yysyntax_error): Use yy_table_value_is_error_.
The zero condition was mishandled before.
* data/yacc.c (yyis_pact_ninf): Rename to...
(yypact_value_is_default): ... this.
(yyis_table_ninf): Rename to...
(yytable_value_is_error): ... this, and check for value zero
besides just YYTABLE_NINF.
(yysyntax_error): Update for rename to yytable_value_is_error.
The zero condition was mishandled before.
(yyparse): Update for renames. No behavioral changes.
* src/tables.h: Improve comments about yypact, yytable, etc.
more. Most importantly, say yytable value of zero means syntax
error not default action.
Eric Blake [Thu, 20 Aug 2009 15:48:49 +0000 (09:48 -0600)]
Import latest m4/m4.m4.
* submodules/autoconf: Update to autoconf 2.64.
* configure.ac (M4_GNU_OPTION): New define.
* src/output.c (output_skeleton): Use it to resolve FIXME.
* NEWS: Mention this.
Joel E. Denny [Thu, 20 Aug 2009 00:37:28 +0000 (20:37 -0400)]
Fix complaints about escape sequences.
Discussed starting at
<http://lists.gnu.org/archive/html/bison-patches/2009-08/msg00036.html>.
* src/scan-gram.l (SC_ESCAPED_STRING, SC_ESCAPED_CHARACTER):
For a \0 and similar escape sequences meaning the null
character, report an invalid escape sequence instead of an
invalid null character because the latter does not actually
appear in the user's input.
In all escape sequence complaints, don't escape the initial
backslash, and don't quote when the sequence appears at the end
of the complaint line unless there's whitespace that quotearg
won't escape.
Consistently say "invalid" not "unrecognized".
Consistently prefer "empty character literal" over "extra
characters in character literal" warning for invalid escape
sequences; that is, consistently discard those sequences.
* tests/input.at (Bad escapes in literals): New.
Akim Demaille [Wed, 19 Aug 2009 12:24:15 +0000 (14:24 +0200)]
variables: simplify the upgrade of namespace into api.namespace.
This patch simplifies "variables: rename namespace as api.namespace",
commit 67501061076ba46355cfd9f9361c7eed861b389c.
Suggested by Joel E. Denny in
http://lists.gnu.org/archive/html/bison-patches/2009-07/msg00006.html
* src/muscle-tab.c (muscle_percent_variable_update): New.
(muscle_percent_define_insert): Use it in replacement of the
previous tr invocation.
Remove variable_tr, no longer needed.
* data/bison.m4 (b4_percent_define_copy_, b4_percent_define_copy):
Remove.
* data/c++.m4: No longer handle namespace -> api.namespace.
* tests/input.at (%define backward compatibility): Check that
namespace is treated as api.namespace.
Akim Demaille [Wed, 19 Aug 2009 11:34:48 +0000 (13:34 +0200)]
2009-08-19 Akim Demaille <demaille@gostai.com>
doc: %initial-action to initialize yylloc.
Reported by Bill Allombert.
* doc/bison.texinfo: Set fill-column to 76.
(Location Type): Document the use of %initial-action to initialize
yylloc.
Akim Demaille [Sun, 16 Aug 2009 05:36:39 +0000 (07:36 +0200)]
lalr1.cc: get rid of yyparse's yystate.
yystate and yystack_[0].state are equal, keep only the latter.
The former was also used as a temporary variable to compute the
post-reduction state. Move this computation into an auxiliary
function.
* data/glr.c (yyLRgotoState): Fuse variable definition and first
assignment.
* data/lalr1.cc (yy_lr_goto_state_): New.
(yyparse): Use it.
Replace remaining uses of yystate by yystate_[0].state.
Remove the former.
Akim Demaille [Wed, 12 Aug 2009 16:00:40 +0000 (18:00 +0200)]
lalr1.cc: destroy $$ when YYERROR is called.
* data/lalr1.cc (yyreduce): Compute the resulting state before
running the user action so that yylhs is a valid symbol.
(yyerrorlab): Since yylhs is complete (it knows its type), we can
simply call yy_destroy_ to destroy $$ on YYERROR invocations.
* tests/c++.at (AT_CHECK_VARIANTS): Test YYERROR with variants.
Joel E. Denny [Tue, 18 Aug 2009 22:29:54 +0000 (18:29 -0400)]
maint: update for gnulib's recent update-copyright changes
* gnulib: Update.
* .x-update-copyright (COPYING): Add as it's no longer implied
when .x-update-copyright is present.
* cfg.mk (update-copyright-local): Remove, now ignored.
(update-copyright): Declare update-b4-copyright as a dependency.
Akim Demaille [Mon, 17 Aug 2009 07:22:41 +0000 (09:22 +0200)]
build: lower gettext requirements.
Bison was uselessly requiring the formatstring macros from
gettext, which resulted in mo files not being installed on systems
that perfectly supported Bison mo files. Lower the requirement.
http://lists.gnu.org/archive/html/bug-bison/2009-08/msg00006.html
* configure.ac: Require need-ngettext instead of
need-formatstring-macros.
Reported by Martin Jabocs.
Suggested by Bruno Haible.
* INSTALL: Restructure.
(Internationalization): New.
(cherry picked from commit b9e42bb439643b6b193ba44696c370bbb35d2ec0)
Joel E. Denny [Sun, 9 Aug 2009 00:19:01 +0000 (20:19 -0400)]
Make it easier to write deterministic tests.
Continues Akim's work from his 2009-06-10 commits.
* src/reader.c (check_and_convert_grammar): Don't add any
symbols after the first symbols_do invocation.
* src/symtab.c (symbols_sorted): New static global.
(user_token_number_redeclaration): Update comments.
(symbol_from_uniqstr): If a new symbol is being created, assert
that symbols_sorted hasn't been allocated yet.
(symbols_free): Free symbols_sorted.
(symbols_cmp, symbols_cmp_qsort): New functions.
(symbols_do): Sort symbol_table into symbols_sorted on first
invocation.
* tests/input.at (Numbered tokens): Recombine tests now that the
output should be deterministic across multiple numbers.
Akim Demaille [Wed, 12 Aug 2009 12:47:08 +0000 (14:47 +0200)]
build: fix the generation of the documentation.
Some of our targets use "bison --help", but they can't depend on
"bison" itself (to avoid additional requirements on the user), so
they used to call "make src/bison" in the commands. Then
concurrent builds may fail: one make might be aiming one of its
jobs at compiling src/bison, and another job at generating the man
page. If the latter is faster than the former, then we have two
makes that concurrently try to compile src/bison.
This might also be a more convincing explanation for the failure
described in the patch "build: fix paths".
* Makefile.am (SUFFIXES): Initialize.
* build-aux/move-if-change: New, symlink to gnulib's.
* build-aux/local.mk: Ship it.
* doc/common.x: Remove, merged into...
* doc/bison.x: here.
* doc/local.mk (doc/bison.help): New.
($(CROSS_OPTIONS_TEXI)): Depend on it.
Use src/bison.
(.x.1): Replace with...
(doc/bison.1): this explicit, simpler, target.
(common_dep): Remove, inlined where appropriate.
(SUFFIXES, PREPATH): Remove, unused.
* configure.ac (gl_PREFIXED_LIBOBJS): Don't rename it, rather,
change the value of...
(gl_LIBOBJS): this.
Adjust more variables.
* etc/prefix-gnulib-mk (prefix_assignment): Don't rename
gl_LIBOBJS.
(prefix): Also transform rules whose targets have slashes.
Use $prefix liberally.
Map @MKDIR_P@ to $(MKDIR_P).
Prefix directories that are mkdir'd.
When using $(top_builddir) inconsistently, Make (including GNU
Make) is sometimes confused. As a result it may want to build
lib/libbison.la and $(top_builddir)/lib/libbison.la (the same
file, different names) concurrently, which, amusingly enough,
might end with: