Autogenerated filename string symbol is incompatible with some assemblers #15799
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huonw
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lnicola
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Oct 17, 2024
fix: Do not consider mutable usage of deref to `*mut T` as deref_mut Fixes rust-lang#15799 We are doing some heuristics for deciding whether the given deref is deref or deref_mut here; https://github.com/rust-lang/rust-analyzer/blob/5982d9c420d0dc90739171829f0d2e9c80d98979/crates/hir-ty/src/infer/mutability.rs#L182-L200 But this heuristic is erroneous if we are dereferencing to a mut ptr and normally those cases are filtered out here as builtin; https://github.com/rust-lang/rust-analyzer/blob/5982d9c420d0dc90739171829f0d2e9c80d98979/crates/hir-ty/src/mir/lower/as_place.rs#L165-L177 Howerver, this works not so well if the given dereferencing is double dereferencings like the case in the rust-lang#15799. ```rust struct WrapPtr(*mut u32); impl core::ops::Deref for WrapPtr { type Target = *mut u32; fn deref(&self) -> &Self::Target { &self.0 } } fn main() { let mut x = 0u32; let wrap = WrapPtr(&mut x); unsafe { **wrap = 6; } } ``` Here are two - outer and inner - dereferences here, and the outer dereference is marked as deref_mut because there is an assignment operation. And this deref_mut marking is propagated into the inner dereferencing. In the later MIR lowering, the outer dereference is filtered out as it's expr type is `*mut u32`, but the expr type in the inner dereference is an ADT, so this false-mutablility is not filtered out. This PR cuts propagation of this false mutablilty chain if the expr type is mut ptr. Since this happens before the resolve_all, it may have some limitations when the expr type is determined as mut ptr at the very end of inferencing, but I couldn't find simple fix for it 🤔
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The assembler for the Gameboy Advance specifically, part of devkitARM.
rustc outputs the LLVM IR constant :
@"strName(956)" = internal constant [8 x i8] c"hello.rs"This is faithfully translated to
This version of
ascan't deal with quotes and brackets in symbol names. For this assembler it'll be necessary to mangle any offending symbol names.The text was updated successfully, but these errors were encountered: