From: Paul Eggert <eggert@cs.ucla.edu>
Date: Mon, 17 Dec 2001 19:43:23 +0000 (+0000)
Subject: Document that YYDEBUG must be defined to a nonzero value.
X-Git-Tag: before-m4-back-end~109
X-Git-Url: https://git.saurik.com/bison.git/commitdiff_plain/4947ebdb4ccb37b60b375ffb94172418677a841b
Document that YYDEBUG must be defined to a nonzero value.
---
diff --git a/doc/bison.1 b/doc/bison.1
index 927a128f..93eaf201 100644
--- a/doc/bison.1
+++ b/doc/bison.1
@@ -262,9 +262,9 @@ and so on.
.ns
.TP
.B \-\-debug
-Output a definition of the macro
+In the parser file, define the macro
.B YYDEBUG
-into the parser file,
+to 1 if it is not already defined,
so that the debugging facilities are compiled.
.TP
.B \-v
diff --git a/doc/bison.rnh b/doc/bison.rnh
index c90bd085..23efa323 100644
--- a/doc/bison.rnh
+++ b/doc/bison.rnh
@@ -56,7 +56,8 @@ foo_tab.c.
.indent -1
2 /DEBUG
.skip
-Output a definition of the macro YYDEBUG into the parser file,
+In the parser file,
+define the macro YYDEBUG to 1 if it is not already defined,
so that the debugging facilities are compiled.
.skip
.indent -1
diff --git a/doc/bison.texinfo b/doc/bison.texinfo
index 609f870b..4aca74ce 100644
--- a/doc/bison.texinfo
+++ b/doc/bison.texinfo
@@ -708,8 +708,8 @@ headers. On some non-@sc{gnu} hosts, @code{<alloca.h>},
@code{<stddef.h>}, and @code{<stdlib.h>} are included as needed to
declare memory allocators and related types. In the same situation,
C++ parsers may include @code{<cstddef>} and @code{<cstdlib>} instead.
-Other system headers may be included if you define @code{YYDEBUG}
-(@pxref{Debugging, ,Debugging Your Parser}).
+Other system headers may be included if you define @code{YYDEBUG} to a
+nonzero value (@pxref{Debugging, ,Debugging Your Parser}).
@node Stages
@section Stages in Using Bison
@@ -3236,9 +3236,9 @@ directives:
@table @code
@item %debug
-Output a definition of the macro @code{YYDEBUG} into the parser file, so
-that the debugging facilities are compiled. @xref{Debugging, ,Debugging
-Your Parser}.
+In the parser file, define the macro @code{YYDEBUG} to 1 if it is not
+already defined, so that the debugging facilities are compiled.
+@xref{Debugging, ,Debugging Your Parser}.
@item %defines
Write an extra output file containing macro definitions for the token
@@ -4925,20 +4925,23 @@ If a Bison grammar compiles properly but doesn't do what you want when it
runs, the @code{yydebug} parser-trace feature can help you figure out why.
To enable compilation of trace facilities, you must define the macro
-@code{YYDEBUG} when you compile the parser. You could use @samp{-DYYDEBUG=1}
-as a compiler option or you could put @samp{#define YYDEBUG 1} in the prologue
-of the grammar file (@pxref{Prologue, , The Prologue}). Alternatively, use the
-@samp{-t} option when you run Bison (@pxref{Invocation, ,Invoking Bison}).
-We always define @code{YYDEBUG} so that debugging is always possible.
+@code{YYDEBUG} to a nonzero value when you compile the parser. You
+could use @samp{-DYYDEBUG=1} as a compiler option or you could put
+@samp{#define YYDEBUG 1} in the prologue of the grammar file
+(@pxref{Prologue, , The Prologue}). Alternatively, use the @samp{-t}
+option when you run Bison (@pxref{Invocation, ,Invoking Bison}) or the
+@code{%debug} declaration (@pxref{Decl Summary, ,Bison Declaration
+Summary}). We suggest that you always define @code{YYDEBUG} so that
+debugging is always possible.
The trace facility outputs messages with macro calls of the form
@code{YYFPRINTF (YYSTDERR, @var{format}, @var{args})} where
@var{format} and @var{args} are the usual @code{printf} format and
-arguments. If you define @code{YYDEBUG} but do not define
-@code{YYFPRINTF}, @code{<stdio.h>} is automatically included and the
-macros are defined to @code{fprintf} and @code{stderr}. In the same
-situation, C++ parsers include @code{<cstdio.h>} instead, and use
-@code{std::fprintf} and @code{std::stderr}.
+arguments. If you define @code{YYDEBUG} to a nonzero value but do not
+define @code{YYFPRINTF}, @code{<stdio.h>} is automatically included
+and the macros are defined to @code{fprintf} and @code{stderr}. In
+the same situation, C++ parsers include @code{<cstdio.h>} instead, and
+use @code{std::fprintf} and @code{std::stderr}.
Once you have compiled the program with trace facilities, the way to
request a trace is to store a nonzero value in the variable @code{yydebug}.
@@ -5099,9 +5102,9 @@ you are developing Bison.
@item -t
@itemx --debug
-Output a definition of the macro @code{YYDEBUG} into the parser file, so
-that the debugging facilities are compiled. @xref{Debugging, ,Debugging
-Your Parser}.
+In the parser file, define the macro @code{YYDEBUG} to 1 if it is not
+already defined, so that the debugging facilities are compiled.
+@xref{Debugging, ,Debugging Your Parser}.
@item --locations
Pretend that @code{%locations} was specified. @xref{Decl Summary}.