diff --git a/dlls/d3dcompiler_43/asmshader.y b/dlls/d3dcompiler_43/asmshader.y
index f33be2259d9..373eea84412 100644
--- a/dlls/d3dcompiler_43/asmshader.y
+++ b/dlls/d3dcompiler_43/asmshader.y
@@ -65,6 +65,8 @@ int asmshader_lex(void);
 
 %}
 
+%define api.prefix {asmshader_}
+
 %union {
     struct {
         float           val;
diff --git a/dlls/d3dcompiler_43/ppl.l b/dlls/d3dcompiler_43/ppl.l
index 1797b98eebf..a1f5298a1ab 100644
--- a/dlls/d3dcompiler_43/ppl.l
+++ b/dlls/d3dcompiler_43/ppl.l
@@ -225,7 +225,7 @@ typedef struct macexpstackentry {
  * Prototypes
  */
 static void newline(int);
-static int make_number(int radix, YYSTYPE *val, const char *str, int len);
+static int make_number(int radix, PPY_STYPE *val, const char *str, int len);
 static void put_buffer(const char *s, int len);
 /* Buffer management */
 static void push_buffer(pp_entry_t *ppp, char *filename, char *incname, int pop);
@@ -829,7 +829,7 @@ static void newline(int dowrite)
  *
  *-------------------------------------------------------------------------
  */
-static int make_number(int radix, YYSTYPE *val, const char *str, int len)
+static int make_number(int radix, PPY_STYPE *val, const char *str, int len)
 {
 	int is_l  = 0;
 	int is_ll = 0;
diff --git a/dlls/d3dcompiler_43/ppy.y b/dlls/d3dcompiler_43/ppy.y
index d520883faab..77c8dfd6190 100644
--- a/dlls/d3dcompiler_43/ppy.y
+++ b/dlls/d3dcompiler_43/ppy.y
@@ -111,6 +111,8 @@ static int	nmacro_args;
 
 %}
 
+%define api.prefix {ppy_}
+
 %union{
 	int		sint;
 	unsigned int	uint;
diff --git a/dlls/jscript/cc_parser.y b/dlls/jscript/cc_parser.y
index dd72f61b03b..46354f479ee 100644
--- a/dlls/jscript/cc_parser.y
+++ b/dlls/jscript/cc_parser.y
@@ -30,6 +30,7 @@ WINE_DEFAULT_DEBUG_CHANNEL(jscript);
 
 %lex-param { parser_ctx_t *ctx }
 %parse-param { parser_ctx_t *ctx }
+%define api.prefix {cc_parser_}
 %define api.pure
 %start CCExpr
 
diff --git a/dlls/jscript/parser.y b/dlls/jscript/parser.y
index 0ebdc2b932b..fb2e1bd5929 100644
--- a/dlls/jscript/parser.y
+++ b/dlls/jscript/parser.y
@@ -128,13 +128,14 @@ static expression_t *new_literal_expression(parser_ctx_t*,literal_t*);
 static expression_t *new_array_literal_expression(parser_ctx_t*,element_list_t*,int);
 static expression_t *new_prop_and_value_expression(parser_ctx_t*,property_list_t*);
 
-#define YYLTYPE unsigned
+#define PARSER_LTYPE unsigned
 #define YYLLOC_DEFAULT(Cur, Rhs, N) Cur = YYRHSLOC((Rhs), (N) ? 1 : 0)
 
 %}
 
 %lex-param { parser_ctx_t *ctx }
 %parse-param { parser_ctx_t *ctx }
+%define api.prefix {parser_}
 %define api.pure
 %start Script
 
diff --git a/dlls/msi/cond.y b/dlls/msi/cond.y
index 636999a104f..c7c9045ff52 100644
--- a/dlls/msi/cond.y
+++ b/dlls/msi/cond.y
@@ -114,6 +114,7 @@ static void value_free( struct value val )
 
 %lex-param { COND_input *info }
 %parse-param { COND_input *info }
+%define api.prefix {cond_}
 %define api.pure
 
 %union
@@ -125,7 +126,7 @@ static void value_free( struct value val )
     BOOL bool;
 }
 
-%token COND_SPACE COND_EOF
+%token COND_SPACE
 %token COND_OR COND_AND COND_NOT COND_XOR COND_IMP COND_EQV
 %token COND_LT COND_GT COND_EQ COND_NE COND_GE COND_LE
 %token COND_ILT COND_IGT COND_IEQ COND_INE COND_IGE COND_ILE
@@ -134,7 +135,7 @@ static void value_free( struct value val )
 %token COND_PERCENT COND_DOLLARS COND_QUESTION COND_AMPER COND_EXCLAM
 %token <str> COND_IDENT <str> COND_NUMBER <str> COND_LITER
 
-%nonassoc COND_ERROR COND_EOF
+%nonassoc COND_ERROR
 
 %type <bool> expression boolean_term boolean_factor
 %type <value> value
diff --git a/dlls/msi/sql.y b/dlls/msi/sql.y
index 5b5c8bd7f8e..885593a9d18 100644
--- a/dlls/msi/sql.y
+++ b/dlls/msi/sql.y
@@ -58,6 +58,7 @@ static struct expr * EXPR_wildcard( void *info );
 
 %lex-param { SQL_input *info }
 %parse-param { SQL_input *info }
+%define api.prefix {sql_}
 %define api.pure
 
 %union
diff --git a/dlls/msxml3/xslpattern.h b/dlls/msxml3/xslpattern.h
index daf6433cd8c..7d2ba5bc739 100644
--- a/dlls/msxml3/xslpattern.h
+++ b/dlls/msxml3/xslpattern.h
@@ -38,7 +38,7 @@ typedef struct _parser_param {
     int err;
 } parser_param;
 
-#define YYSTYPE xmlChar*
+#define XSLPATTERN_STYPE xmlChar*
 #define YY_EXTRA_TYPE parser_param*
 
 int  xslpattern_lex(xmlChar**, void*) DECLSPEC_HIDDEN;
diff --git a/dlls/msxml3/xslpattern.l b/dlls/msxml3/xslpattern.l
index c02c6747099..ddf1503c1ba 100644
--- a/dlls/msxml3/xslpattern.l
+++ b/dlls/msxml3/xslpattern.l
@@ -26,6 +26,7 @@
 WINE_DEFAULT_DEBUG_CHANNEL(msxml);
 
 #define SCAN    xslpattern_get_extra(yyscanner)
+#define YYSTYPE XSLPATTERN_STYPE
 
 #define YY_INPUT(tok_buf, tok_len, max) \
         do { \
diff --git a/dlls/msxml3/xslpattern.y b/dlls/msxml3/xslpattern.y
index 94136fd12c4..9abf43cad35 100644
--- a/dlls/msxml3/xslpattern.y
+++ b/dlls/msxml3/xslpattern.y
@@ -66,6 +66,7 @@ static void xslpattern_error(parser_param* param, void const* scanner, char cons
 
 %start XSLPattern
 
+%define api.prefix {xslpattern_}
 %define api.pure
 %parse-param {parser_param* p}
 %parse-param {void* scanner}
diff --git a/dlls/vbscript/parser.y b/dlls/vbscript/parser.y
index 796e9d5ee5e..948f27288b0 100644
--- a/dlls/vbscript/parser.y
+++ b/dlls/vbscript/parser.y
@@ -81,13 +81,14 @@ static statement_t *link_statements(statement_t*,statement_t*);
 
 #define CHECK_ERROR if(((parser_ctx_t*)ctx)->hres != S_OK) YYABORT
 
-#define YYLTYPE unsigned
+#define PARSER_LTYPE unsigned
 #define YYLLOC_DEFAULT(Cur, Rhs, N) Cur = YYRHSLOC((Rhs), (N) ? 1 : 0)
 
 %}
 
 %lex-param { parser_ctx_t *ctx }
 %parse-param { parser_ctx_t *ctx }
+%define api.prefix {parser_}
 %define api.pure
 %start Program
 
diff --git a/dlls/wbemprox/wql.y b/dlls/wbemprox/wql.y
index 7a6d7cf505c..d1b608ac832 100644
--- a/dlls/wbemprox/wql.y
+++ b/dlls/wbemprox/wql.y
@@ -217,6 +217,7 @@ static int wql_lex( void *val, struct parser *parser );
 %lex-param { struct parser *ctx }
 %parse-param { struct parser *ctx }
 %define parse.error verbose
+%define api.prefix {wql_}
 %define api.pure
 
 %union
diff --git a/programs/winedbg/dbg.y b/programs/winedbg/dbg.y
index 3e6ef34b836..a34fb83d108 100644
--- a/programs/winedbg/dbg.y
+++ b/programs/winedbg/dbg.y
@@ -35,6 +35,8 @@ static void parser(const char*);
 
 %}
 
+%define api.prefix {dbg_}
+
 %union
 {
     struct dbg_lvalue   lvalue;
diff --git a/tools/makedep.c b/tools/makedep.c
index 5a286c3c343..589ea7a7514 100644
--- a/tools/makedep.c
+++ b/tools/makedep.c
@@ -2622,15 +2622,15 @@ static void output_source_y( struct makefile *make, struct incl_file *source, co
     if (find_include_file( make, header ))
     {
         output( "%s: %s\n", obj_dir_path( make, header ), source->filename );
-        output( "\t%s%s -p %s_ -o %s.tab.c -d %s\n",
-                cmd_prefix( "BISON" ), bison, obj, obj_dir_path( make, obj ), source->filename );
+        output( "\t%s%s -o %s.tab.c -d %s\n",
+                cmd_prefix( "BISON" ), bison, obj_dir_path( make, obj ), source->filename );
         output( "%s.tab.c: %s %s\n", obj_dir_path( make, obj ),
                 source->filename, obj_dir_path( make, header ));
         strarray_add( &make->clean_files, header );
     }
     else output( "%s.tab.c: %s\n", obj_dir_path( make, obj ), source->filename );
 
-    output( "\t%s%s -p %s_ -o $@ %s\n", cmd_prefix( "BISON" ), bison, obj, source->filename );
+    output( "\t%s%s -o $@ %s\n", cmd_prefix( "BISON" ), bison, source->filename );
 }
 
 
diff --git a/tools/widl/parser.y b/tools/widl/parser.y
index fa863921c92..e16e30e98a9 100644
--- a/tools/widl/parser.y
+++ b/tools/widl/parser.y
@@ -120,6 +120,9 @@ static statement_list_t *parameterized_type_stmts = NULL;
 static typelib_t *current_typelib;
 
 %}
+
+%define api.prefix {parser_}
+
 %union {
 	attr_t *attr;
 	attr_list_t *attr_list;
@@ -480,7 +483,7 @@ typedecl:
 
 cppquote: tCPPQUOTE '(' aSTRING ')'		{ $$ = $3; }
 	;
-import_start: tIMPORT aSTRING ';'		{ assert(yychar == YYEMPTY);
+import_start: tIMPORT aSTRING ';'		{ assert(yychar == PARSER_EMPTY);
 						  $$ = xmalloc(sizeof(struct _import_t));
 						  $$->name = $2;
 						  $$->import_performed = do_import($2);
diff --git a/tools/wmc/mcy.y b/tools/wmc/mcy.y
index 79d3679afdf..52f28ca6b74 100644
--- a/tools/wmc/mcy.y
+++ b/tools/wmc/mcy.y
@@ -95,6 +95,8 @@ static struct cp_xlat *find_cpxlat(int lan);
 
 %}
 
+%define api.prefix {mcy_}
+
 %union {
 	WCHAR		*str;
 	unsigned	num;
diff --git a/tools/wrc/parser.y b/tools/wrc/parser.y
index 51bf09efd98..944cffd0064 100644
--- a/tools/wrc/parser.y
+++ b/tools/wrc/parser.y
@@ -200,6 +200,9 @@ static resource_t *build_fontdir(resource_t **fnt, int nfnt);
 static int rsrcid_to_token(int lookahead);
 
 %}
+
+%define api.prefix {parser_}
+
 %union{
 	string_t	*str;
 	int		num;
@@ -487,11 +490,11 @@ resource
 		 * want_id because we already have a lookahead that
 		 * cannot be undone.
 		 */
-		if(yychar != YYEMPTY && yychar != tNL)
+		if(yychar != PARSER_EMPTY && yychar != tNL)
 			dont_want_id = 1;
 
 		if(yychar == tNL)
-			yychar = YYEMPTY;	/* Could use 'yyclearin', but we already need the*/
+			yychar = PARSER_EMPTY;	/* Could use 'yyclearin', but we already need the*/
 						/* direct access to yychar in rule 'usrcvt' below. */
 		else if(yychar == tIDENT)
 			parser_warning("LANGUAGE statement not delimited with newline; next identifier might be wrong\n");
@@ -2722,7 +2725,7 @@ static int rsrcid_to_token(int lookahead)
 	int token;
 
 	/* Get a token if we don't have one yet */
-	if(lookahead == YYEMPTY)
+	if(lookahead == PARSER_EMPTY)
 		lookahead = yylex();
 
 	/* Only numbers are possibly interesting */
diff --git a/tools/wrc/ppl.l b/tools/wrc/ppl.l
index f27a2b48476..35c3fd6fb44 100644
--- a/tools/wrc/ppl.l
+++ b/tools/wrc/ppl.l
@@ -240,7 +240,7 @@ typedef struct macexpstackentry {
  * Prototypes
  */
 static void newline(int);
-static int make_number(int radix, YYSTYPE *val, const char *str, int len);
+static int make_number(int radix, PPY_STYPE *val, const char *str, int len);
 static void put_buffer(const char *s, int len);
 /* Buffer management */
 static void push_buffer(pp_entry_t *ppp, char *filename, char *incname, int pop);
@@ -796,7 +796,7 @@ static void newline(int dowrite)
  *
  *-------------------------------------------------------------------------
  */
-static int make_number(int radix, YYSTYPE *val, const char *str, int len)
+static int make_number(int radix, PPY_STYPE *val, const char *str, int len)
 {
 	int is_l  = 0;
 	int is_ll = 0;
diff --git a/tools/wrc/ppy.y b/tools/wrc/ppy.y
index a4b834d7f6c..ac4423d724f 100644
--- a/tools/wrc/ppy.y
+++ b/tools/wrc/ppy.y
@@ -115,6 +115,8 @@ static int	nmacro_args;
 
 %}
 
+%define api.prefix {ppy_}
+
 %union{
 	int		sint;
 	unsigned int	uint;