xref: /aosp_15_r20/bionic/tests/libs/elftls_tprel.cpp (revision 8d67ca893c1523eb926b9080dbe4e2ffd2a27ba1)
1  /*
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28  
29  // This shared object tests TPREL relocations in the dynamic linker. It's always
30  // part of static TLS.
31  
32  // For accesses to these variables, the bfd and lld linkers generate a TPREL
33  // relocation with no symbol but a non-zero addend.
34  __attribute__((tls_model("initial-exec"))) static __thread int tls_var_1 = 3;
35  __attribute__((tls_model("initial-exec"))) static __thread int tls_var_2 = 7;
36  
bump_static_tls_var_1()37  extern "C" int bump_static_tls_var_1() {
38    return ++tls_var_1;
39  }
40  
bump_static_tls_var_2()41  extern "C" int bump_static_tls_var_2() {
42    return ++tls_var_2;
43  }
44  
45  __attribute__((tls_model("initial-exec"), weak)) extern "C" __thread int missing_weak_tls;
46  
missing_weak_tls_addr()47  extern "C" int* missing_weak_tls_addr() {
48    // The dynamic linker should resolve a TPREL relocation to this symbol to 0,
49    // which this function adds to the thread pointer.
50    return &missing_weak_tls;
51  }
52