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diff --git a/BaseTools/Source/C/VfrCompile/Pccts/KNOWN_PROBLEMS.txt b/BaseTools/Source/C/VfrCompile/Pccts/KNOWN_PROBLEMS.txt deleted file mode 100644 index 5a9b22e1bd..0000000000 --- a/BaseTools/Source/C/VfrCompile/Pccts/KNOWN_PROBLEMS.txt +++ /dev/null @@ -1,241 +0,0 @@ -
- =======================================================
- Known Problems In PCCTS - Last revised 14 November 1998
- =======================================================
-
-#17. The dlg fix for handling characters up to 255 is incorrect.
-
- See item #207.
-
- Reported by Frank Hartmann.
-
-#16. A note about "&&" predicates (Mike Dimmick)
-
- Mike Dimmick has pointed out a potential pitfall in the use of the
- "&&" style predicate. Consider:
-
- r0: (g)? => <<P>>? r1
- | ...
- ;
- r1: A | B;
-
- If the context guard g is not a subset of the lookahead context for r1
- (in other words g is neither A nor B) then the code may execute r1
- even when the lookahead context is not satisfied. This is an error
- by the person coding the grammer, and the error should be reported to
- the user, but it isn't. expect. Some examples I've run seem to
- indicate that such an error actually results in the rule becoming
- unreachable.
-
- When g is properly coded the code is correct, the problem is when g
- is not properly coded.
-
- A second problem reported by Mike Dimmick is that the test for a
- failed validation predicate is equivalent to a test on the predicate
- along. In other words, if the "&&" has not been hoisted then it may
- falsely report a validation error.
-
-#15. (Changed in MR23) Warning for LT(i), LATEXT(i) in token match actions
-
- An bug (or at least an oddity) is that a reference to LT(1), LA(1),
- or LATEXT(1) in an action which immediately follows a token match
- in a rule refers to the token matched, not the token which is in
- the lookahead buffer. Consider:
-
- r : abc <<action alpha>> D <<action beta>> E;
-
- In this case LT(1) in action alpha will refer to the next token in
- the lookahead buffer ("D"), but LT(1) in action beta will refer to
- the token matched by D - the preceding token.
-
- A warning has been added which warns users about this when an action
- following a token match contains a reference to LT(1), LA(1), or LATEXT(1).
-
- This behavior should be changed, but it appears in too many programs
- now. Another problem, perhaps more significant, is that the obvious
- fix (moving the consume() call to before the action) could change the
- order in which input is requested and output appears in existing programs.
-
- This problem was reported, along with a fix by Benjamin Mandel
- (beny@sd.co.il). However, I felt that changing the behavior was too
- dangerous for existing code.
-
-#14. Parsing bug in dlg
-
- THM: I have been unable to reproduce this problem.
-
- Reported by Rick Howard Mijenix Corporation (rickh@mijenix.com).
-
- The regular expression parser (in rexpr.c) fails while
- trying to parse the following regular expression:
-
- {[a-zA-Z]:}(\\\\[a-zA-Z0-9]*)+
-
- See my comment in the following excerpt from rexpr.c:
-
- /*
- * <regExpr> ::= <andExpr> ( '|' {<andExpr>} )*
- *
- * Return -1 if syntax error
- * Return 0 if none found
- * Return 1 if a regExrp was found
- */
- static
- regExpr(g)
- GraphPtr g;
- {
- Graph g1, g2;
-
- if ( andExpr(&g1) == -1 )
- {
- return -1;
- }
-
- while ( token == '|' )
- {
- int a;
- next();
- a = andExpr(&g2);
- if ( a == -1 ) return -1; /* syntax error below */
- else if ( !a ) return 1; /* empty alternative */
- g1 = BuildNFA_AorB(g1, g2);
- }
-
- if ( token!='\0' ) return -1;
- *****
- ***** It appears to fail here becuause token is 125 - the closing '}'
- ***** If I change it to:
- ***** if ( token!='\0' && token!='}' && token!= ')' ) return -1;
- *****
- ***** It succeeds, but I'm not sure this is the corrrect approach.
- *****
- *g = g1;
- return 1;
- }
-
-#13. dlg reports an invalid range for: [\0x00-\0xff]
-
- Diagnosed by Piotr Eljasiak (eljasiak@no-spam.zt.gdansk.tpsa.pl):
-
- Fixed in MR16.
-
-#12. Strings containing comment actions
-
- Sequences that looked like C style comments appearing in string
- literals are improperly parsed by antlr/dlg.
-
- << fprintf(out," /* obsolete */ ");
-
- For this case use:
-
- << fprintf(out," \/\* obsolete \*\/ ");
-
- Reported by K.J. Cummings (cummings@peritus.com).
-
-#11. User hook for deallocation of variables on guess fail
-
- The mechanism outlined in Item #108 works only for
- heap allocated variables.
-
-#10. Label re-initialization in ( X {y:Y} )*
-
- If a label assignment is optional and appears in a
- (...)* or (...)+ block it will not be reset to NULL
- when it is skipped by a subsequent iteration.
-
- Consider the example:
-
- ( X { y:Y })* Z
-
- with input:
-
- X Y X Z
-
- The first time through the block Y will be matched and
- y will be set to point to the token. On the second
- iteration of the (...)* block there is no match for Y.
- But y will not be reset to NULL, as the user might
- expect, it will contain a reference to the Y that was
- matched in the first iteration.
-
- The work-around is to manually reset y:
-
- ( X << y = NULL; >> { y:Y } )* Z
-
- or
-
- ( X ( y:Y | << y = NULL; >> /* epsilon */ ) )* Z
-
- Reported by Jeff Vincent (JVincent@novell.com).
-
-#9. PCCTAST.h PCCTSAST::setType() is a noop
-
-#8. #tokdefs with ~Token and .
-
- THM: I have been unable to reproduce this problem.
-
- When antlr uses #tokdefs to define tokens the fields of
- #errclass and #tokclass do not get properly defined.
- When it subsequently attempts to take the complement of
- the set of tokens (using ~Token or .) it can refer to
- tokens which don't have names, generating a fatal error.
-
-#7. DLG crashes on some invalid inputs
-
- THM: In MR20 have fixed the most common cases.
-
- The following token defintion will cause DLG to crash.
-
- #token "()"
-
- Reported by Mengue Olivier (dolmen@bigfoot.com).
-
-#6. On MS systems \n\r is treated as two new lines
-
- Fixed.
-
-#5. Token expressions in #tokclass
-
- #errclass does not support TOK1..TOK2 or ~TOK syntax.
- #tokclass does not support ~TOKEN syntax
-
- A workaround for #errclass TOK1..TOK2 is to use a
- #tokclass.
-
- Reported by Dave Watola (dwatola@amtsun.jpl.nasa.gov)
-
-#4. A #tokdef must appear "early" in the grammar file.
-
- The "early" section of the grammar file is the only
- place where the following directives may appear:
-
- #header
- #first
- #tokdefs
- #parser
-
- Any other kind of statement signifiies the end of the
- "early" section.
-
-#3. Use of PURIFY macro for C++ mode
-
- Item #93 of the CHANGES_FROM_1.33 describes the use of
- the PURIFY macro to zero arguments to be passed by
- upward inheritance.
-
- #define PURIFY(r, s) memset((char *) &(r), '\0', (s));
-
- This may not be the right thing to do for C++ objects that
- have constructors. Reported by Bonny Rais (bonny@werple.net.au).
-
- For those cases one should #define PURIFY to be an empty macro
- in the #header or #first actions.
-
-#2. Fixed in 1.33MR10 - See CHANGES_FROM_1.33 Item #80.
-
-#1. The quality of support for systems with 8.3 file names leaves
- much to be desired. Since the kit is distributed using the
- long file names and the make file uses long file names it requires
- some effort to generate. This will probably not be changed due
- to the large number of systems already written using the long
- file names.
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