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Permit ty::Bool in const generics for v0 mangling #77452

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Merged
merged 1 commit into from
Oct 3, 2020
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Permit ty::Bool in const generics for v0 mangling #77452

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1 change: 1 addition & 0 deletions compiler/rustc_symbol_mangling/src/v0.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -504,6 +504,7 @@ impl Printer<'tcx> for SymbolMangler<'tcx> {

match ct.ty.kind() {
ty::Uint(_) => {}
ty::Bool => {}
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If this is all that's required, can we also add ty::Char and ty::Int, or do these need special attention?

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ty::Int seems reasonable, though we might want to change mangling to express signed-ness (so you get foo<-1> in perf top or whatever, not foo<255>). I think we do not want to encode char with the bits so I would like to hold off on it for now.

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So both seem harder than just bool, which encoding with 0/1 seems quite reasonable.

_ => {
bug!("symbol_names: unsupported constant of type `{}` ({:?})", ct.ty, ct);
}
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18 changes: 18 additions & 0 deletions src/test/ui/symbol-names/issue-76365.rs
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@@ -0,0 +1,18 @@
// check-pass
// revisions: legacy v0
//[legacy]compile-flags: -Z symbol-mangling-version=legacy --crate-type=lib
//[v0]compile-flags: -Z symbol-mangling-version=v0 --crate-type=lib

#![feature(min_const_generics)]

pub struct Bar<const F: bool>;

impl Bar<true> {
pub fn foo() {}
}

impl<const F: bool> Bar<F> {
pub fn bar() {}
}

fn main() {}