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Adding more than `isize::MAX` to a pointer is UB and this is possible on 32-bit platforms when most of the address space is allocated. This commit updates to using `wrapping_*` methods which are not UB to add more than `isize::MAX`. This is another alternative fix to 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
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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
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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
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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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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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Adding more than
isize::MAXto a pointer is UB and this is possible on 32-bit platforms when most of the address space is allocated. This commit updates to usingwrapping_*methods which are not UB to add more thanisize::MAX. This is another alternative fix to rust-lang/rust#144199.