[Bug modula2/114296] New: ICE when attempting to create a constant set with a variable element

[Bug modula2/114296] New: ICE when attempting to create a constant set with a variable element

[gaius at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114296

            Bug ID: 114296
           Summary: ICE when attempting to create a constant set with a
                    variable element
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: modula2
          Assignee: gaius at gcc dot gnu.org
          Reporter: gaius at gcc dot gnu.org
  Target Milestone: ---

As reported on the mailing list attempting to create a constant set using a
variable will cause an ICE.

MODULE tiny2 ;

VAR
   x: CARDINAL ;
   ch: CHAR ;
BEGIN
   x := 6 ;
   ch := {7 .. x};
END tiny2.

[Bug modula2/114296] ICE when attempting to create a constant set with a variable element

[gaius at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114296

Gaius Mulley <gaius at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2024-03-10
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1

[Bug modula2/114296] ICE when attempting to create a constant set with a variable element

[gaius at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114296

--- Comment #1 from Gaius Mulley <gaius at gcc dot gnu.org> ---
Created attachment 57719
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57719&action=edit
Proposed fix

Here is the proposed fix.  It corrects the virtual token creation for the
aggregate constant and also corrects tokens for constructor components.

[Bug modula2/114296] ICE when attempting to create a constant set with a variable element

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114296

--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Gaius Mulley <gaius@gcc.gnu.org>:

https://gcc.gnu.org/g:f065c582d9c8e0a4fee7ee563c584ee3b1975bea

commit r14-9506-gf065c582d9c8e0a4fee7ee563c584ee3b1975bea
Author: Gaius Mulley <gaiusmod2@gmail.com>
Date:   Sun Mar 17 14:49:23 2024 +0000

    PR modula2/114296 ICE when attempting to create a constant set with a
variable element

    This patch corrects the virtual token creation for the aggregate constant
    and also corrects tokens for constructor components.

    gcc/m2/ChangeLog:

            PR modula2/114296
            * gm2-compiler/M2ALU.mod (ElementsSolved): Add tokenno parameter.
            Add constant checks and generate error messages.
            (EvalSetValues): Pass tokenno parameter to ElementsSolved.
            * gm2-compiler/M2LexBuf.mod (stop): New procedure.
            (MakeVirtualTok): Call stop if caret = BadTokenNo.
            * gm2-compiler/M2Quads.def (BuildNulExpression): Add tokpos
            parameter.
            (BuildSetStart): Ditto.
            (BuildEmptySet): Ditto.
            (BuildConstructorEnd): Add startpos parameter.
            (BuildTypeForConstructor): Add tokpos parameter.
            * gm2-compiler/M2Quads.mod (BuildNulExpression): Add tokpos
            parameter and push tokpos to the quad stack.
            (BuildSetStart): Add tokpos parameter and push tokpos.
            (BuildSetEnd): Rewrite.
            (BuildEmptySet): Add tokpos parameter and push tokpos with
            the set type.
            (BuildConstructorStart): Pop typepos.
            (BuildConstructorEnd): Add startpos parameter.
            Create valtok from startpos and cbratokpos.
            (BuildTypeForConstructor): Add tokpos parameter.
            * gm2-compiler/M2Range.def (InitAssignmentRangeCheck): Rename
            d to des and e to expr.
            Add destok and exprtok parameters.
            * gm2-compiler/M2Range.mod (InitAssignmentRangeCheck): Rename
            d to des and e to expr.
            Add destok and exprtok parameters.
            Save destok and exprtok into range record.
            (FoldAssignment): Pass exprtok to TryDeclareConstant.
            * gm2-compiler/P3Build.bnf (ComponentValue): Rewrite.
            (Constructor): Rewrite.
            (ConstSetOrQualidentOrFunction): Rewrite.
            (SetOrQualidentOrFunction): Rewrite.
            * gm2-compiler/PCBuild.bnf (ConstSetOrQualidentOrFunction):
Rewrite.
            (SetOrQualidentOrFunction): Rewrite.
            * gm2-compiler/PHBuild.bnf (Constructor): Rewrite.
            (ConstSetOrQualidentOrFunction): Rewrite.

    gcc/testsuite/ChangeLog:

            PR modula2/114296
            * gm2/pim/fail/badtype2.mod: New test.

    Signed-off-by: Gaius Mulley <gaiusmod2@gmail.com>

[Bug modula2/114296] ICE when attempting to create a constant set with a variable element

[gaius at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114296

Gaius Mulley <gaius at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #3 from Gaius Mulley <gaius at gcc dot gnu.org> ---
Closing now that the patch has been applied.  The ICE was caused by assuming
that the set elements were constants.  The patch contains a check and also
improves the token accuracy of the set sub expression.

The test code above now causes the following correct error message:

$ gm2 tiny2.mod 
tiny2.mod:8:10: error: a constant set can only contain constant set elements,
‘x’ is not a constant
    8 |    ch := {7 .. x};
      |          ^~~~~~~~