diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:02:58 +0000 |
commit | 698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch) | |
tree | 173a775858bd501c378080a10dca74132f05bc50 /src/test/ui/borrowck/borrowck-assign-comp.rs | |
parent | Initial commit. (diff) | |
download | rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip |
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/test/ui/borrowck/borrowck-assign-comp.rs')
-rw-r--r-- | src/test/ui/borrowck/borrowck-assign-comp.rs | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/src/test/ui/borrowck/borrowck-assign-comp.rs b/src/test/ui/borrowck/borrowck-assign-comp.rs new file mode 100644 index 000000000..98bb2d85a --- /dev/null +++ b/src/test/ui/borrowck/borrowck-assign-comp.rs @@ -0,0 +1,36 @@ +struct Point { x: isize, y: isize } + +fn a() { + let mut p = Point {x: 3, y: 4}; + let q = &p; + + // This assignment is illegal because the field x is not + // inherently mutable; since `p` was made immutable, `p.x` is now + // immutable. Otherwise the type of &_q.x (&isize) would be wrong. + p.x = 5; //~ ERROR cannot assign to `p.x` because it is borrowed + q.x; +} + +fn c() { + // this is sort of the opposite. We take a loan to the interior of `p` + // and then try to overwrite `p` as a whole. + + let mut p = Point {x: 3, y: 4}; + let q = &p.y; + p = Point {x: 5, y: 7};//~ ERROR cannot assign to `p` because it is borrowed + p.x; // silence warning + *q; // stretch loan +} + +fn d() { + // just for completeness's sake, the easy case, where we take the + // address of a subcomponent and then modify that subcomponent: + + let mut p = Point {x: 3, y: 4}; + let q = &p.y; + p.y = 5; //~ ERROR cannot assign to `p.y` because it is borrowed + *q; +} + +fn main() { +} |