Change Details

This example ``` #include <stdio.h> #include <stdint.h> static inline char *tag(char *ptr) { return (char*)(((uintptr_t)ptr & 0xffffffffffff) | (69L << 56)); } int main() { char v = 'x'; printf("ptr %p val %c\n", &v, *(&v)); printf("ptr %p\n", tag(&v)); printf("val %c\n", *tag(&v)); return 0; } ``` no longer segfaults on the last dereference.

This example ``` #include <stdio.h> #include <stdint.h> static inline char *tag(char *ptr) { return (char*)(((uintptr_t)ptr & 0xffffffffffff) | (69L << 56)); } int main() { char v = 'x'; printf("ptr %p val %c\n", &v, *(&v)); printf("ptr %p\n", tag(&v)); printf("val %c\n", *tag(&v)); return 0; } ``` no longer segfaults on the last dereference. UPD: also, I got HWASAN working :) [my current llvm80 patches are here](https://github.com/myfreeweb/freebsd-ports-dank/commit/fe03024636f0a2b82325ce6f91f96c1bfbdd9fb7) (I'll try to keep the link here up to date)

This example ``` #include <stdio.h> #include <stdint.h> static inline char *tag(char *ptr) { return (char*)(((uintptr_t)ptr & 0xffffffffffff) | (69L << 56)); } int main() { char v = 'x'; printf("ptr %p val %c\n", &v, *(&v)); printf("ptr %p\n", tag(&v)); printf("val %c\n", *tag(&v)); return 0; } ``` no longer segfaults on the last dereference. UPD: also, I got HWASAN working :) [my current llvm80 patches are here](https://github.com/myfreeweb/freebsd-ports-dank/commit/fe03024636f0a2b82325ce6f91f96c1bfbdd9fb7) (I'll try to keep the link here up to date)