🍒 [TSan] Fix TSan instrumenting pointers from non-default address spaces #12068
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llvm#174518) Casting a pointer to a different address space is a nice trick to prevent an access from being instrumented by sanitizers such as ASan. However, this trick is currently broken, as the test demonstrates. A minimal C PoC of the issue is: ``` void access(void *p) { auto tmp = (unsigned long __attribute__((address_space(1))) volatile *)p; *tmp = 0; } ``` Under fsanitize=address, the access does not get instrumented, but under fsanitize=thread, it does. (Note: Before this patch, this test will actually hit a CallInst assertion if you have them turned on, because the TSan runtime functions are defined to take pointer arguments, and non-default address space pointers are not compatible). rdar://166743781 (cherry picked from commit 99e8aa5)
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@swift-ci please test |
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@swift-ci please test macOS |
DanBlackwell
approved these changes
Jan 7, 2026
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@swift-ci please test macOS |
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@swift-ci please test macOS |
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@swift-ci please test macOS |
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@swift-ci please test macOS |
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Cherry-pick llvm#174518