Bug report . Bison 1.875

[Laurent D. Michel]

Summary:

The generated code does not compile. 
Compiler used gcc-2.95.4
Environment Debian/sid and Debian/woody

The grammar.y file is intended to generate code for a C++ parser. The parser is tagged pure. 

Here is the output I get when compiling:

compiling C grammar.tab.c
/tmp/tmpParserldm: In function `int yyparse(LocParser *)':
/tmp/tmpParserldm:4796: ANSI C++ forbids declaration `yylerrsp' with no type
/tmp/tmpParserldm:4796: conflicting types for `int yylerrsp'
/tmp/tmpParserldm:2753: previous declaration as `struct YYLTYPE * yylerrsp'
/tmp/tmpParserldm:4796: initialization to `int' from `YYLTYPE *' lacks a cast
/tmp/tmpParserldm:4797: invalid type argument of `unary *'
/tmp/tmpParserldm:4839: invalid operands `int' and `YYLTYPE *' to binary `operator -'
/tmp/tmpParserldm:4839: invalid operands `int' and `YYLTYPE *' to binary `operator -'
/tmp/tmpParserldm:4788: warning: label `yyerrlab1' defined but not used

And here is the compilation command line (around line 4796)

g++-2.95 -c  -Wall -fPIC -g  -Woverloaded-virtual   -I../include -I../data -I../localizer  -I../runtime grammar.tab.c

The code fragment extracted from the c file is:

yyerrlab1:

  /* Suppress GCC warning that yyerrlab1 is unused when no action
     invokes YYERROR.  */
#if defined (__GNUC_MINOR__) && 2093 <= (__GNUC__ * 1000 + __GNUC_MINOR__)
  __attribute__ ((__unused__))
#endif

  yylerrsp = yylsp;
  *++yylerrsp = yyloc;
  goto yyerrlab2;


If I remove the #if defined(....)  that precedes the yylerrsp = yylsp everything works as expected.

I attach the grammar.tab.c file to this email for reference.

Also, I would like to suggest a feature....

I use bison to generate a parser that is used from C++. As such, the yyparse function takes an
argument which happens to be a pointer to the parser object. So far, the yyparse has the prototype

yyparse(void  *YYPARSE_PARAM)

What I usually do is used sed to replace the void in the signature by the type of the parser object (LocParser in this case). It would be nice to have that configurable with a macro such as 

yyparse(YYPARSE_PARAM_TYPE *YYPARSE_PARAM) 

to avoid this sed step.

In any case, many thanks for your help,

Sincerely,

--
Laurent D. Michel <address@hidden>

grammar.tab.c
Description: Text Data

grammar.tab.h
Description: Text Data