tests/libs/elftls_tprel.cpp

/*
 * Copyright (C) 2019 The Android Open Source Project
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// This shared object tests TPREL relocations in the dynamic linker. It's always
// part of static TLS.

// For accesses to these variables, the bfd and lld linkers generate a TPREL
// relocation with no symbol but a non-zero addend.
__attribute__((tls_model("initial-exec"))) static __thread int tls_var_1 = 3;
__attribute__((tls_model("initial-exec"))) static __thread int tls_var_2 = 7;

extern "C" int bump_static_tls_var_1() {
  return ++tls_var_1;
}

extern "C" int bump_static_tls_var_2() {
  return ++tls_var_2;
}

__attribute__((tls_model("initial-exec"), weak)) extern "C" __thread int missing_weak_tls;

extern "C" int* missing_weak_tls_addr() {
  // The dynamic linker should resolve a TPREL relocation to this symbol to 0,
  // which this function adds to the thread pointer.
  return &missing_weak_tls;
}