Skip to content

Fix for issue #7588, "Overflow handling of from_str methods is broken" #9010

New issue

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

Sign up for GitHub

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

Already on GitHub? Sign in to your account

Closed
wants to merge 1 commit into from
Closed

Fix for issue #7588, "Overflow handling of from_str methods is broken" #9010

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
35 changes: 31 additions & 4 deletions src/libstd/num/strconv.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -552,8 +552,18 @@ pub fn from_str_bytes_common<T:NumCast+Zero+One+Eq+Ord+Div<T,T>+
// Detect overflow by comparing to last value, except
// if we've not seen any non-zero digits.
if last_accum != _0 {
if accum_positive && accum <= last_accum { return None; }
if !accum_positive && accum >= last_accum { return None; }
if accum_positive && accum <= last_accum { return NumStrConv::inf(); }
if !accum_positive && accum >= last_accum { return NumStrConv::neg_inf(); }

// Detect overflow by reversing the shift-and-add proccess
if accum_positive &&
(last_accum != ((accum - cast(digit as int))/radix_gen.clone())) {
return NumStrConv::inf();
}
if !accum_positive &&
(last_accum != ((accum + cast(digit as int))/radix_gen.clone())) {
return NumStrConv::neg_inf();
}
}
last_accum = accum.clone();
}
Expand Down Expand Up @@ -597,8 +607,8 @@ pub fn from_str_bytes_common<T:NumCast+Zero+One+Eq+Ord+Div<T,T>+
}

// Detect overflow by comparing to last value
if accum_positive && accum < last_accum { return None; }
if !accum_positive && accum > last_accum { return None; }
if accum_positive && accum < last_accum { return NumStrConv::inf(); }
if !accum_positive && accum > last_accum { return NumStrConv::neg_inf(); }
last_accum = accum.clone();
}
None => match c {
Expand Down Expand Up @@ -702,6 +712,23 @@ mod test {
ExpNone, false, false);
assert_eq!(n, None);
}

#[test]
fn from_str_issue7588() {
let u : Option<u8> = from_str_common("1000", 10, false, false, false,
ExpNone, false, false);
assert_eq!(u, None);
let s : Option<i16> = from_str_common("80000", 10, false, false, false,
ExpNone, false, false);
assert_eq!(s, None);
let f : Option<f32> = from_str_common(
"10000000000000000000000000000000000000000", 10, false, false, false,
ExpNone, false, false);
assert_eq!(f, NumStrConv::inf())
let fe : Option<f32> = from_str_common("1e40", 10, false, false, false,
ExpDec, false, false);
assert_eq!(fe, NumStrConv::inf())
}
}

#[cfg(test)]
Expand Down