tests/libs/elftls_dynamic.cpp

/*
 * Copyright (C) 2019 The Android Open Source Project
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// This shared object test library is dlopen'ed by the main test executable.
// This variable comes from libtest_elftls_shared_var.so, which is part of
// static TLS. Verify that a GD-model access can access the variable.
//
// Accessing the static TLS variable from an solib prevents the static linker
// from relaxing the GD access to IE and lets us test that __tls_get_addr and
// the tlsdesc resolver handle a static TLS variable.
extern "C" __thread int elftls_shared_var;

extern "C" int bump_shared_var() {
  return ++elftls_shared_var;
}

// The static linker denotes the current module by omitting the symbol from
// the DTPMOD/TLSDESC relocations.
static __thread int local_var_1 = 15;
static __thread int local_var_2 = 25;

extern "C" int bump_local_vars() {
  return ++local_var_1 + ++local_var_2;
}

__attribute__((weak)) extern "C" __thread int missing_weak_dyn_tls;

extern "C" int* missing_weak_dyn_tls_addr() {
  return &missing_weak_dyn_tls;
}