Don't allocate the final addresses on wasm #54
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This is intended at being one fix to rust-lang/rust#144199. It's not valid in Rust for an allocation to include the final byte of the address space, so when the final wasm page is allocated it cannot be entirely in use. This fakes the last 16 bytes as un-allocate-able and this is sufficient for resolving rust-lang/rust#144199.
alexcrichton
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Jul 23, 2025
This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address rust-lang#144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes rust-lang#144199
fmease
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Jul 24, 2025
…rk-Simulacrum Update `dlmalloc` dependency of libstd This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address rust-lang#144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes rust-lang#144199
fmease
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Jul 25, 2025
…rk-Simulacrum Update `dlmalloc` dependency of libstd This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address rust-lang#144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes rust-lang#144199
matthiaskrgr
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Jul 25, 2025
…rk-Simulacrum Update `dlmalloc` dependency of libstd This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address rust-lang#144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes rust-lang#144199
tgross35
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Jul 26, 2025
…rk-Simulacrum Update `dlmalloc` dependency of libstd This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address rust-lang#144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes rust-lang#144199
rust-timer
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Jul 26, 2025
Rollup merge of #144364 - alexcrichton:update-dlmalloc, r=Mark-Simulacrum Update `dlmalloc` dependency of libstd This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address #144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes #144199
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Jul 30, 2025
…rk-Simulacrum Update `dlmalloc` dependency of libstd This primarily pulls in alexcrichton/dlmalloc-rs#55 and alexcrichton/dlmalloc-rs#54 to address rust-lang#144199. Notably the highest byte in the wasm address space is no longer allocatable and additionally the allocator internally uses `wrapping_add` instead of `add` on pointers since on 32-bit platforms offsets might be larger than half the address space. Closes rust-lang#144199
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This is intended at being one fix to rust-lang/rust#144199. It's not valid in Rust for an allocation to include the final byte of the address space, so when the final wasm page is allocated it cannot be entirely in use. This fakes the last 16 bytes as un-allocate-able and this is sufficient for resolving rust-lang/rust#144199.