# Wrong form classes for DW_CFA_def_cfa_expression, _expression, and _val_expression

After accepting Issue [230616.1][230616.1], we made the following
editorial changes (among others):

- Section 6.4.2.2, p. 178, bullet 6, line 27 [`DW_CFA_def_cfa_expression`]: exprloc -> exprval.
- Section 6.4.2.3, p. 180, bullet 9, line 13 [`DW_CFA_expression`]: `DW_FORM_block` -> exprloc -> exprval.
- Section 6.4.2.3, p. 180, bullet 10, line 21 [`DW_CFA_val_expression`]: `DW_FORM_block` -> exprloc -> exprval.

Note that Section 6.4 is now 7.4. The page numbers are now closer to 200 and 202.

Also, as a result of [251030.1][251030.1], the form classes were
renamed valexpr and locexpr.

It seems to me that the first two, `DW_CFA_def_cfa_expression` and
`DW_CFA_expression`, should be locexpr, not valexpr. These are
expressions that return a location, not a value. That's the
difference between `DW_CFA_expression` and `DW_CFA_val_expression`:
the first gives a location, and second gives a value.

In Section 8.23, Table 8.29 has `DW_CFA_def_cfa_expression` and
`DW_CFA_expression` taking locexpr (correct, I think), but also
lists `DW_CFA_val_expression` as taking locexpr (wrong, should be
valexpr).

## Proposal

In Section 7.4.2.2 CFA Definition Instructions, bullet 6,
`DW_CFA_def_cfa_expression`, change "valexpr" to "locexpr".

In Section 7.4.2.3 Register Rule Instructions, bullet 9,
`DW_CFA_expression`, change "valexpr" to "locexpr".

(Bullet 10, `DW_CFA_val_expression` is correct.)

In Section 8.23 Call Frame Information, Table 8.29,
in the row for `DW_CFA_val_expression`, change "locexpr" to "valexpr".

(The rows for `DW_CFA_def_cfa_expression` and `DW_CFA_expression` are correct.)

[230616.1]: https://dwarfstd.org/issues/230616.1.html
[251030.1]: https://dwarfstd.org/issues/251030.1.html

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2026-04-27: Accepted.