[compiler-rt] [compiler-rt][rtsan] Use sanitizer internal allocator during rtsan init to avoid segfault in dlsym (PR #98679)

[Fangrui Song via llvm-commits]

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@@ -238,23 +243,35 @@ INTERCEPTOR(int, nanosleep, const struct timespec *rqtp,
 // Memory
 
 INTERCEPTOR(void *, calloc, SIZE_T num, SIZE_T size) {
+  if (rtsan_init_is_running && REAL(calloc) == nullptr)
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MaskRay wrote:

We should define `UseImpl` and use `DlsymAlloc::Use`. See #98415 

https://github.com/llvm/llvm-project/pull/98679