diff --git a/data/bison.m4 b/data/bison.m4
index 80e025c9..cd810501 100644
--- a/data/bison.m4
+++ b/data/bison.m4
@@ -389,11 +389,11 @@ b4_define_flag_if([yacc])               # Whether POSIX Yacc is emulated.
 #
 # The following macros provide access to these values.
 
-# b4_symbol_(NUM, FIELD)
+# _b4_symbol(NUM, FIELD)
 # ----------------------
 # Recover a FIELD about symbol #NUM.  Thanks to m4_indir, fails if
 # undefined.
-m4_define([b4_symbol_],
+m4_define([_b4_symbol],
 [m4_indir([b4_symbol($1, $2)])])
 
 
@@ -404,8 +404,8 @@ m4_define([b4_symbol_],
 m4_define([b4_symbol],
 [m4_case([$2],
          [id],    [m4_do([b4_percent_define_get([api.token.prefix])],
-                         [b4_symbol_([$1], [id])])],
-         [b4_symbol_($@)])])
+                         [_b4_symbol([$1], [id])])],
+         [_b4_symbol($@)])])
 
 
 # b4_symbol_if(NUM, FIELD, IF-TRUE, IF-FALSE)
@@ -443,7 +443,7 @@ m4_define([b4_symbol_action],
                    b4_symbol_if([$1], [has_type],
                                 [m4_dquote(b4_symbol([$1], [type]))]),
                    [(*yylocationp)])dnl
-    b4_symbol_case_([$1])[]dnl
+    _b4_symbol_case([$1])[]dnl
 b4_syncline([b4_symbol([$1], [$2_line])], [b4_symbol([$1], [$2_file])])
       b4_symbol([$1], [$2])
 b4_syncline([@oline@], [@ofile@])
@@ -478,10 +478,10 @@ m4_ifval(m4_defn([b4_actions_]),
 m4_popdef([b4_actions_])dnl
 ])
 
-# b4_symbol_case_(SYMBOL-NUM)
+# _b4_symbol_case(SYMBOL-NUM)
 # ---------------------------
 # Issue a "case NUM" for SYMBOL-NUM.
-m4_define([b4_symbol_case_],
+m4_define([_b4_symbol_case],
 [case b4_symbol([$1], [number]): b4_symbol_tag_comment([$1])])
 ])
 
@@ -536,16 +536,16 @@ m4_define([b4_token_format],
 ## Types.  ##
 ## ------- ##
 
-# b4_type_action_(NUMS)
+# _b4_type_action(NUMS)
 # ---------------------
 # Run actions for the symbol NUMS that all have the same type-name.
 # Skip NUMS that have no type-name.
 #
 # To specify the action to run, define b4_dollar_dollar(NUMBER,
 # TAG, TYPE).
-m4_define([b4_type_action_],
+m4_define([_b4_type_action],
 [b4_symbol_if([$1], [has_type],
-[m4_map([      b4_symbol_case_], [$@])[]dnl
+[m4_map([      _b4_symbol_case], [$@])[]dnl
         b4_dollar_dollar([b4_symbol([$1], [number])],
                          [b4_symbol([$1], [tag])],
                          [b4_symbol([$1], [type])]);
@@ -701,7 +701,7 @@ m4_define([b4_percent_define_use],
 #   b4_percent_define_get([[foo]])
 m4_define([b4_percent_define_get],
 [b4_percent_define_use([$1])dnl
-b4_percent_define_ifdef_([$1],
+_b4_percent_define_ifdef([$1],
                          [m4_indir([b4_percent_define(]$1[)])],
                          [$2])])
 
@@ -755,15 +755,15 @@ m4_define([b4_percent_define_get_syncline],
           [m4_indir([b4_percent_define_syncline(]$1[)])],
           [b4_fatal([[$0: undefined %%define variable '%s']], [$1])])])
 
-# b4_percent_define_ifdef_(VARIABLE, IF-TRUE, [IF-FALSE])
+# _b4_percent_define_ifdef(VARIABLE, IF-TRUE, [IF-FALSE])
 # ------------------------------------------------------
 # If the %define variable VARIABLE is defined, expand IF-TRUE, else expand
 # IF-FALSE.  Don't record usage of VARIABLE.
 #
 # For example:
 #
-#   b4_percent_define_ifdef_([[foo]], [[it's defined]], [[it's undefined]])
-m4_define([b4_percent_define_ifdef_],
+#   _b4_percent_define_ifdef([[foo]], [[it's defined]], [[it's undefined]])
+m4_define([_b4_percent_define_ifdef],
 [m4_ifdef([b4_percent_define(]$1[)],
           [$2],
           [$3])])
@@ -779,7 +779,7 @@ m4_define([b4_percent_define_ifdef_],
 #
 #   b4_percent_define_ifdef([[foo]], [[it's defined]], [[it's undefined]])
 m4_define([b4_percent_define_ifdef],
-[b4_percent_define_ifdef_([$1],
+[_b4_percent_define_ifdef([$1],
                          [b4_percent_define_use([$1])$2],
                          [$3])])
 
@@ -824,7 +824,7 @@ m4_define([b4_percent_define_flag_if],
 #
 #   b4_percent_define_default([[foo]], [[default value]])
 m4_define([b4_percent_define_default],
-[b4_percent_define_ifdef_([$1], [],
+[_b4_percent_define_ifdef([$1], [],
            [m4_define([b4_percent_define(]$1[)], [$2])dnl
             m4_define([b4_percent_define_kind(]$1[)],
                       [m4_default([$3], [keyword])])dnl
@@ -839,19 +839,19 @@ m4_define([b4_percent_define_default],
 # Define b4_NAME_if that executes its $1 or $2 depending whether
 # VARIABLE was %defined.  The characters '.' and `-' in VARIABLE are mapped
 # to '_'.
-m4_define([b4_percent_define_if_define_],
+m4_define([_b4_percent_define_if_define],
 [m4_define(m4_bpatsubst([b4_$1_if], [[-.]], [_]),
            [b4_percent_define_flag_if(m4_default([$2], [$1]),
                                       [$3], [$4])])])
 m4_define([b4_percent_define_if_define],
 [b4_percent_define_default([m4_default([$2], [$1])], [[false]])
-b4_percent_define_if_define_([$1], [$2], $[1], $[2])])
+_b4_percent_define_if_define([$1], [$2], $[1], $[2])])
 
 
 # b4_percent_define_check_kind(VARIABLE, KIND, [DIAGNOSTIC = complain])
 # ---------------------------------------------------------------------
 m4_define([b4_percent_define_check_kind],
-[b4_percent_define_ifdef_([$1],
+[_b4_percent_define_ifdef([$1],
   [m4_if(b4_percent_define_get_kind([$1]), [$2], [],
     [b4_error([m4_default([$3], [complain])],
               b4_percent_define_get_loc([$1]),
@@ -884,7 +884,7 @@ m4_define([b4_percent_define_check_values],
             [_b4_percent_define_check_values(b4_sublist)])])
 
 m4_define([_b4_percent_define_check_values],
-[b4_percent_define_ifdef_([$1],
+[_b4_percent_define_ifdef([$1],
   [b4_percent_define_check_kind(]$1[, [keyword], [deprecated])dnl
    m4_pushdef([b4_good_value], [0])dnl
    m4_if($#, 1, [],
diff --git a/data/c++.m4 b/data/c++.m4
index 4cf51d40..5beb5f0e 100644
--- a/data/c++.m4
+++ b/data/c++.m4
@@ -36,7 +36,7 @@ b4_percent_define_check_kind([parser_class_name], [code], [deprecated])
 # --------------------------
 # Put TEXT in comment. Prefix all the output lines with PREFIX.
 m4_define([b4_comment],
-[b4_comment_([$1], [$2// ], [$2// ])])
+[_b4_comment([$1], [$2// ], [$2// ])])
 
 
 # b4_inline(hh|cc)
diff --git a/data/c-like.m4 b/data/c-like.m4
index 26bab42e..4e476ac8 100644
--- a/data/c-like.m4
+++ b/data/c-like.m4
@@ -17,14 +17,14 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# b4_comment_(TEXT, OPEN, CONTINUE, END)
+# _b4_comment(TEXT, OPEN, CONTINUE, END)
 # --------------------------------------
 # Put TEXT in comment.  Avoid trailing spaces: don't indent empty lines.
 # Avoid adding indentation to the first line, as the indentation comes
 # from OPEN.  That's why we don't patsubst([$1], [^\(.\)], [   \1]).
 #
 # Prefix all the output lines with PREFIX.
-m4_define([b4_comment_],
+m4_define([_b4_comment],
 [$2[]m4_bpatsubst(m4_expand([[$1]]), [
 \(.\)], [
 $3\1])$4])
@@ -34,17 +34,17 @@ $3\1])$4])
 # --------------------------
 # Put TEXT in comment.  Prefix all the output lines with PREFIX.
 m4_define([b4_comment],
-[b4_comment_([$1], [$2/* ], [$2   ], [  */])])
+[_b4_comment([$1], [$2/* ], [$2   ], [  */])])
 
 
 
 
-# b4_dollar_dollar_(VALUE, FIELD, DEFAULT-FIELD)
+# _b4_dollar_dollar(VALUE, FIELD, DEFAULT-FIELD)
 # ----------------------------------------------
 # If FIELD (or DEFAULT-FIELD) is non-null, return "VALUE.FIELD",
 # otherwise just VALUE.  Be sure to pass "(VALUE)" is VALUE is a
 # pointer.
-m4_define([b4_dollar_dollar_],
+m4_define([_b4_dollar_dollar],
 [b4_symbol_value([$1],
                  m4_if([$2], [[]],
                        [[$3]], [[$2]]))])
@@ -56,7 +56,7 @@ m4_define([b4_dollar_dollar_],
 # and b4_at_dollar for LOCATION.
 m4_define([b4_dollar_pushdef],
 [m4_pushdef([b4_dollar_dollar],
-            [b4_dollar_dollar_([$1], m4_dquote($][1), [$2])])dnl
+            [_b4_dollar_dollar([$1], m4_dquote($][1), [$2])])dnl
 m4_pushdef([b4_at_dollar], [$3])dnl
 ])
 m4_define([b4_dollar_popdef],
diff --git a/data/lalr1.cc b/data/lalr1.cc
index 15fd6fb9..1a5138bf 100644
--- a/data/lalr1.cc
+++ b/data/lalr1.cc
@@ -106,7 +106,7 @@ b4_dollar_pushdef([yysym.value],
                    b4_symbol_if([$1], [has_type],
                                 [m4_dquote(b4_symbol([$1], [type]))]),
                    [yysym.location])dnl
-      b4_symbol_case_([$1])
+      _b4_symbol_case([$1])
 b4_syncline([b4_symbol([$1], [$2_line])], [b4_symbol([$1], [$2_file])])
         b4_symbol([$1], [$2])
 b4_syncline([@oline@], [@ofile@])
diff --git a/data/variant.hh b/data/variant.hh
index 4ba3f006..d573666b 100644
--- a/data/variant.hh
+++ b/data/variant.hh
@@ -29,7 +29,7 @@ m4_define([b4_symbol_variant],
             [$2.$3< $][3 > (m4_shift3($@))])dnl
 switch ($1)
     {
-b4_type_foreach([b4_type_action_])[]dnl
+b4_type_foreach([_b4_type_action])[]dnl
       default:
         break;
     }
@@ -299,15 +299,15 @@ m4_define([b4_symbol_value_template],
 ## ------------- ##
 
 
-# b4_symbol_constructor_declare_(SYMBOL-NUMBER)
+# _b4_symbol_constructor_declare(SYMBOL-NUMBER)
 # ---------------------------------------------
 # Declare the overloaded version of make_symbol for the (common) type of
 # these SYMBOL-NUMBERS.  Use at class-level.
-m4_define([b4_symbol_constructor_declare_],
+m4_define([_b4_symbol_constructor_declare],
 [b4_symbol_if([$1], [is_token], [b4_symbol_if([$1], [has_id],
 [    static
     symbol_type
-    make_[]b4_symbol_([$1], [id]) (dnl
+    make_[]_b4_symbol([$1], [id]) (dnl
 b4_join(b4_symbol_if([$1], [has_type],
                      [YY_COPY (b4_symbol([$1], [type])) v]),
         b4_locations_if([YY_COPY (location_type) l])));
@@ -321,18 +321,18 @@ b4_join(b4_symbol_if([$1], [has_type],
 # Use at class-level.
 m4_define([b4_symbol_constructor_declare],
 [    // Symbol constructors declarations.
-b4_symbol_foreach([b4_symbol_constructor_declare_])])
+b4_symbol_foreach([_b4_symbol_constructor_declare])])
 
 
 
-# b4_symbol_constructor_define_(SYMBOL-NUMBER)
+# _b4_symbol_constructor_define(SYMBOL-NUMBER)
 # --------------------------------------------
 # Define symbol constructor for this SYMBOL-NUMBER.
-m4_define([b4_symbol_constructor_define_],
+m4_define([_b4_symbol_constructor_define],
 [b4_symbol_if([$1], [is_token], [b4_symbol_if([$1], [has_id],
 [  inline
   b4_parser_class_name::symbol_type
-  b4_parser_class_name::make_[]b4_symbol_([$1], [id]) (dnl
+  b4_parser_class_name::make_[]_b4_symbol([$1], [id]) (dnl
 b4_join(b4_symbol_if([$1], [has_type],
                      [YY_COPY (b4_symbol([$1], [type])) v]),
         b4_locations_if([YY_COPY (location_type) l])))
@@ -376,4 +376,4 @@ m4_define([b4_basic_symbol_constructor_define],
 # Define the overloaded versions of make_symbol for all the value types.
 m4_define([b4_symbol_constructor_define],
 [  // Implementation of make_symbol for each symbol type.
-b4_symbol_foreach([b4_symbol_constructor_define_])])
+b4_symbol_foreach([_b4_symbol_constructor_define])])
diff --git a/data/yacc.c b/data/yacc.c
index e72b098b..15b0c160 100644
--- a/data/yacc.c
+++ b/data/yacc.c
@@ -237,11 +237,11 @@ m4_define([b4_declare_parser_state_variables], [b4_pure_if([[
     YYSIZE_T yyes_capacity;]])])
 
 
-# b4_declare_yyparse_push_
+# _b4_declare_yyparse_push
 # ------------------------
 # Declaration of yyparse (and dependencies) when using the push parser
 # (including in pull mode).
-m4_define([b4_declare_yyparse_push_],
+m4_define([_b4_declare_yyparse_push],
 [[#ifndef YYPUSH_MORE_DEFINED
 # define YYPUSH_MORE_DEFINED
 enum { YYPUSH_MORE = 4 };
@@ -265,18 +265,18 @@ b4_function_declare([b4_prefix[pstate_delete]], [[void]],
                    [[b4_prefix[pstate *ps]], [[ps]]])dnl
 ])
 
-# b4_declare_yyparse_
+# _b4_declare_yyparse
 # -------------------
 # When not the push parser.
-m4_define([b4_declare_yyparse_],
+m4_define([_b4_declare_yyparse],
 [b4_function_declare(b4_prefix[parse], [int], b4_parse_param)])
 
 
 # b4_declare_yyparse
 # ------------------
 m4_define([b4_declare_yyparse],
-[b4_push_if([b4_declare_yyparse_push_],
-            [b4_declare_yyparse_])[]dnl
+[b4_push_if([_b4_declare_yyparse_push],
+            [_b4_declare_yyparse])[]dnl
 ])