Merge branch 'branch-2.6' into maint

* origin/branch-2.6: (24 commits)
  tests: calc: modernize the use of locations
  tests: remove useless location initializations
  lalr1.cc: always initialize yylval.
  tests: check that C and C++ objects can be linked together.
  yacc.c: also disable -Wuninitialized.
  glr.cc, yacc.c: initialize yylloc properly
  yacc.c, glr.c: a better YY_LOCATION_PRINT
  yacc.c: simplify initialization
  doc: formatting changes
  c++: fix position operator signatures
  tests: remove useless location initialization.
  tests: fix locations in C
  tests: handle %parse-param in the generated yyerror
  tests: simplifications
  grammars: fix display of nul character in error message
  tests: sort
  tests: cosmetic changes
  comment changes
  autoconf: update
  gnulib: update
  ...

Conflicts:
	NEWS
	gnulib
	tests/named-refs.at
	tests/regression.at

tests/local.at

@@ -119,6 +119,7 @@ m4_pushdef([AT_SKEL_CC_IF],
 [m4_bmatch([$3], [%language "[Cc]\+\+"\|%skeleton "[a-z0-9]+\.cc"], [$1], [$2])])
 m4_pushdef([AT_SKEL_JAVA_IF],
 [m4_bmatch([$3], [%language "[Jj][Aa][Vv][Aa]"\|%skeleton "[a-z0-9]+\.java"], [$1], [$2])])
+# The target language: "c", "c++", or "java".
 m4_pushdef([AT_LANG],
 [AT_SKEL_JAVA_IF([java],
                  [AT_SKEL_CC_IF([c++],
@@ -140,6 +141,12 @@ m4_pushdef([AT_LOCATION_TYPE_IF],
 [m4_bmatch([$3], [%define \(api\.location\.type\|location_type\)], [$1], [$2])])
 m4_pushdef([AT_PARAM_IF],
 [m4_bmatch([$3], [%parse-param], [$1], [$2])])
+# Comma-terminated list of formals parse-parameters.
+# E.g., %parse-param { int x } {int y} -> "int x, int y, ".
+m4_pushdef([AT_PARSE_PARAMS])
+m4_bpatsubst([$3], [%parse-param { *\([^{}]*[^{} ]\) *}],
+             [m4_append([AT_PARSE_PARAMS], [\1, ])])
+
 m4_pushdef([AT_PURE_IF],
 [m4_bmatch([$3], [%define  *api\.pure\|%pure-parser],
            [m4_bmatch([$3], [%define  *api\.pure *"?false"?], [$2], [$1])],
@@ -241,6 +248,7 @@ m4_popdef([AT_GLR_OR_PARAM_IF])
 m4_popdef([AT_PURE_AND_LOC_IF])
 m4_popdef([AT_LOCATION_TYPE_IF])
 m4_popdef([AT_LOCATION_IF])
+m4_popdef([AT_PARSE_PARAMS])
 m4_popdef([AT_PARAM_IF])
 m4_popdef([AT_LEXPARAM_IF])
 m4_popdef([AT_YACC_IF])
@@ -350,7 +358,7 @@ static
 # Must be called inside a AT_BISON_OPTION_PUSHDEFS/POPDEFS pair.
 m4_define([AT_YYERROR_FORMALS],
 [m4_case(AT_LANG,
-[c], [AT_YYERROR_ARG_LOC_IF([AT_YYLTYPE *llocp, ])[const char *msg]])[]dnl
+[c], [AT_YYERROR_ARG_LOC_IF([AT_YYLTYPE *llocp, ])AT_PARSE_PARAMS [const char *msg]])[]dnl
 ])
 
 m4_define([AT_YYERROR_PROTOTYPE],
@@ -374,16 +382,11 @@ m4_define([AT_YYERROR_DEFINE],
 /* A C error reporting function.  */
 static
 ]AT_YYERROR_PROTOTYPE[
-{
-]AT_YYERROR_SEES_LOC_IF([[
-  fprintf (stderr, "%d.%d",
-           ]AT_LOC_FIRST_LINE[, ]AT_LOC_FIRST_COLUMN[);
-  if (]AT_LOC_FIRST_LINE[ != ]AT_LOC_LAST_LINE[)
-    fprintf (stderr, "-%d.%d",
-             ]AT_LOC_LAST_LINE[,  ]AT_LOC_LAST_COLUMN[ - 1);
-  else if (]AT_LOC_FIRST_COLUMN[ != ]AT_LOC_LAST_COLUMN[ - 1)
-    fprintf (stderr, "-%d",
-             ]AT_LOC_LAST_COLUMN[ - 1);
+{]m4_bpatsubst(m4_defn([AT_PARSE_PARAMS]),
+              [[^,]+[^A-Za-z_0-9]\([A-Za-z_][A-Za-z_0-9]*\), *], [
+  YYUSE(\1);])dnl
+AT_YYERROR_SEES_LOC_IF([[
+  YY_LOCATION_PRINT (stderr, ]AT_LOC[);
   fprintf (stderr, ": ");]])[
   fprintf (stderr, "%s\n", msg);
 }]],
@@ -680,6 +683,44 @@ m4_define([AT_FULL_COMPILE],
 ])
 
 
+
+# AT_SKIP_IF_CANNOT_LINK_C_AND_CXX
+# --------------------------------
+# Check that we can link together C and C++ objects.
+m4_define([AT_SKIP_IF_CANNOT_LINK_C_AND_CXX],
+[AT_DATA([c-and-cxx.h],
+[[#ifdef __cplusplus
+extern "C"
+{
+#endif
+  int fortytwo (void);
+#ifdef __cplusplus
+}
+#endif
+]])
+AT_DATA([c-only.c],
+[[#include "c-and-cxx.h"
+int
+main (void)
+{
+  return fortytwo () == 42 ? 0 : 1;
+}
+]])
+AT_DATA([cxx-only.cc],
+[[#include "c-and-cxx.h"
+int fortytwo ()
+{
+  return 42;
+}
+]])
+AT_COMPILE([c-only.o], [c-only.c])
+AT_COMPILE_CXX([cxx-only.o], [cxx-only.cc])
+AT_CHECK([$CXX $CXXFLAGS $CPPFLAGS $LDFLAGS c-only.o cxx-only.o -o c-and-cxx ||
+          exit 77], [ignore], [ignore])
+AT_CHECK([./c-and-cxx])
+])
+
+
 ## ---------------------------- ##
 ## Running a generated parser.  ##
 ## ---------------------------- ##