Mark dlsym with __attribute__((noinline)).
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In some circumstances (e.g. under higher optimization modes when compiled with LLVM), `dlsym` gets inlined into `libvirtcpuid_init_dso`. When this happens, dlsym's use of `__builtin_return_address(0)` no longer returns the address of `dlsym` and instead returns the address of `libvirtcpuid_init_dso`. When that happens, `_dl_sym` fails to find the next `dlsym` and the process crashes.
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In some circumstances (e.g. under higher optimization modes when
compiled with LLVM),
dlsymgets inlined intolibvirtcpuid_init_dso.When this happens, dlsym's use of
__builtin_return_address(0)nolonger returns the address of
dlsymand instead returns the address oflibvirtcpuid_init_dso. When that happens,_dl_symfails to find thenext
dlsymand the process crashes.