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* src/symtab.h (SALIAS, SUNDEF): Rename as...

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(USER_NUMBER_ALIAS, USER_NUMBER_UNDEFINED): these.
Adjust dependencies.
* src/output.c (token_definitions_output): Be sure not to output a
`#define 'a'' when fed with `%token 'a' "a"'.
* tests/regression.at (Token definitions): New.
This commit is contained in:
Akim Demaille
2002-05-04 08:48:04 +00:00
parent 8bb936e4f7
commit b87f8b2159
9 changed files with 89 additions and 68 deletions
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32
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@@ -277,38 +277,6 @@ Rewrite the reader in Flex/Bison. There will be delicate parts, in
particular, expect the scanner to be hard to write. Many interesting
features cannot be implemented without such a new reader.
* Problems with aliases
From: "Baum, Nathan I" <s0009525@chelt.ac.uk>
Subject: Token Alias Bug
To: "'bug-bison@gnu.org'" <bug-bison@gnu.org>
I've noticed a bug in bison. Sadly, our eternally wise sysadmins won't let
us use CVS, so I can't find out if it's been fixed already...
Basically, I made a program (in flex) that went through a .y file looking
for "..."-tokens, and then outputed a %token
line for it. For single-character ""-tokens, I reasoned, I could just use
[%token 'A' "A"]. However, this causes Bison to output a [#define 'A' 65],
which cppp chokes on, not unreasonably. (And even if cppp didn't choke, I
obviously wouldn't want (char)'A' to be replaced with (int)65 throughout my
code.
Bison normally forgoes outputing a #define for a character token. However,
it always outputs an aliased token -- even if the token is an alias for a
character token. We don't want that. The problem is in /output.c/, as I
recall. When it outputs the token definitions, it checks for a character
token, and then checks for an alias token. If the character token check is
placed after the alias check, then it works correctly.
Alias tokens seem to be something of a kludge. What about an [%alias "..."]
command...
%alias T_IF "IF"
Hmm. I can't help thinking... What about a --generate-lex option that
creates an .l file for the alias tokens used... (Or an option to make a
gperf file, etc...)
* Presentation of the report file
From: "Baum, Nathan I" <s0009525@chelt.ac.uk>
Subject: Token Alias Bug