Skip to content

Overflow checking failed on #[repr(i64)] enums #23235

New issue

Have a question about this project? # for a free GitHub account to open an issue and contact its maintainers and the community.

#

By clicking “#”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? # to your account

Jump to bottom
Closed
theemathas opened this issue Mar 9, 2015 · 1 comment · Fixed by #23863
Closed

Overflow checking failed on #[repr(i64)] enums #23235

theemathas opened this issue Mar 9, 2015 · 1 comment · Fixed by #23863
Labels
A-type-system Area: Type system

Comments

@theemathas
Copy link
Contributor

Code:

#[repr(i64)]
enum X {
    A = 0x_7FFF_FFFF_FFFF_FFFF,
    B,
}

fn main() {
    println!("{}", X::A as i64);
    println!("{}", X::B as i64);
}

Output:

9223372036854775807
-9223372036854775808

This is the opposite of #23221
@kmcallister kmcallister added the A-type-system Area: Type system label Mar 10, 2015
@theemathas theemathas mentioned this issue Mar 18, 2015
Closed
@pnkfelix pnkfelix mentioned this issue Mar 29, 2015
Closed
@pnkfelix pnkfelix mentioned this issue Mar 31, 2015
Merged
@pnkfelix
Copy link
Member

cc #23897

pnkfelix added a commit to pnkfelix/rust that referenced this issue Mar 31, 2015
@pnkfelix
Added type-specific overflow checks when computing enum discriminant …
8601802 
…values.

Moved such overflow checking into one place (in `rustc::middle::ty`,
since it needs to be run on-demand during `const_eval` in some
scenarios), and revised `rustc_typeck` accordingly.

(Note that we only check for overflow if program did not provide a
discriminant value explicitly.)

Fix rust-lang#23030

Fix rust-lang#23221

Fix rust-lang#23235
pnkfelix added a commit to pnkfelix/rust that referenced this issue Apr 1, 2015
@pnkfelix
Added type-specific overflow checks when computing enum discriminant …
4e04d57 
…values.

Moved such overflow checking into one place (in `rustc::middle::ty`,
since it needs to be run on-demand during `const_eval` in some
scenarios), and revised `rustc_typeck` accordingly.

(Note that we only check for overflow if program did not provide a
discriminant value explicitly.)

Fix rust-lang#23030

Fix rust-lang#23221

Fix rust-lang#23235
alexcrichton added a commit to alexcrichton/rust that referenced this issue Apr 1, 2015
@alexcrichton
rollup merge of rust-lang#23863: pnkfelix/arith-oflo-const-eval
4f643d7 
const_eval : add overflow-checking for {`+`, `-`, `*`, `/`, `<<`, `>>`}.

One tricky detail here: There is some duplication of labor between `rustc::middle::const_eval` and `rustc_trans::trans::consts`. It might be good to explore ways to try to factor out the common structure to the two passes (by abstracting over the particular value-representation used in the compile-time interpreter).

----

Update: Rebased atop rust-lang#23841

Fix rust-lang#22531

Fix rust-lang#23030

Fix rust-lang#23221

Fix rust-lang#23235
# for free to join this conversation on GitHub. Already have an account? # to comment
Assignees
No one assigned
Labels
A-type-system Area: Type system
Projects
None yet
Milestone
No milestone
3 participants
@pnkfelix @kmcallister @theemathas