If a macro arg came in the middle of a symbol or at the end, e.g. "SYM\1", it would say that the symbol was not defined. This was because it wasn't looking up the macro arg's value correctly.
A reference to an invalid macro argument (\ not followed by a digit
between 1 and 9) will cause an access outside of the bounds of the
currentmacroargs array in sym_FindMacroArg().
Macro arg references are processed in two places:
In CopyMacroArg(): called when scanning tokens between "", {} and
arguments of a macro call. The only problem here is that it accepts \0
as valid and so calls sym_FindMacroArg with a invalid value.
In PutMacroArg(): called by the lexer automata when it encounters a
token matching \\[0-9]? (in other cases than above). So not only it
accepts \0 but also \ alone.
Memo: In setuplex(), a rule is defined with a regex composed of up to
three ranges of chars and takes the form:
[FirstRange]
or [FirstRange][SecondRange]?
or [FirstRange]([SecondRange][Range]*)?
On scanning, when several rules match, the first longuest one is
choosen.
Regression test:
1)
SECTION "HOME", HOME
db "\0"
2)
SECTION "HOME", HOME
db \A
3)
SECTION "HOME", HOME
db \
The problem occurs when \@ is accessed outside the definition of a
macro and is not between "" or {}, or when it is used in an argument of
a macro call, i.e. when the access is processed by PutUniqueArg().
PutUniqueArg(), puts back the string value of \@ to the lexer's buffer
(to substitute \@ by the unique label string).
When \@ is not defined, sym_FindMacroArg(-1) returns NULL, which
yyunputstr() doesn't expect and crashes.
Solution:
Generate an error when \@ is not defined.
Regression test:
SECTION "HOME", HOME
ld a,\@
Will segfault.
On the fixed version, it will return an error as \@ is not available.
Merging lai's source with this one is very irritating because
they have different indentation styles. I couldn't find what profile
vegard used for his version, so I used these flags (which should bring
the source close to KNF):
-bap
-br
-ce
-ci4
-cli0
-d0
-di0
-i8
-ip
-l79
-nbc
-ncdb
-ndj
-ei
-nfc1
-nlp
-npcs
-psl
-sc
-sob
