On my Android 11 device only shows up in logcat and not under bash shell

05-02 15:43:39.495  7843  7843 E linker  : "/data/data/com.termux/files/home/bin/hello": ignoring DT_PREINIT_ARRAY in shared library!

Below is a simpler reproduction case (for Termux Docker which the warning will show under bash shell):

~ $ cat test_dlopen.c
#include <stdio.h>
#include <dlfcn.h>

int main(int argc, char *argv[]) {
    puts("Yes its running");
    if (argc > 2) {
        printf("%s only accepts a path to so file\n", argv[0]);
        return -1;
    }
    printf("Trying to access %s\n", argv[1]);
    void *so_handle = dlopen(argv[1], RTLD_NOW);
    if (!so_handle) {
        puts("Something went wrong");
        fprintf(stderr, "%s\n" , dlerror());
    } else {
        puts("Access ok");
    }
    return 0;
}
~ $ cat exe.c
int main() {};
~ $ cat lib.c
int foo();
~ $ cc exe.c -o exe
~ $ cc lib.c -o lib -shared

~ $ readelf -d exe lib

File: exe
Dynamic section at offset 0x690 contains 25 entries:
  Tag                Type              Name/Value
  0x000000000000001d (RUNPATH)         Library runpath: [/data/data/com.termux/files/usr/lib]
  0x0000000000000001 (NEEDED)          Shared library: [libdl.so]
  0x0000000000000001 (NEEDED)          Shared library: [libc.so]
  0x000000000000001e (FLAGS)           BIND_NOW
  0x000000006ffffffb (FLAGS_1)         NOW PIE
  0x0000000000000015 (DEBUG)           0x0
  0x0000000000000017 (JMPREL)          0x468
  0x0000000000000002 (PLTRELSZ)        72 (bytes)
  0x0000000000000003 (PLTGOT)          0x2820
  0x0000000000000014 (PLTREL)          RELA
  0x0000000000000006 (SYMTAB)          0x358
  0x000000000000000b (SYMENT)          24 (bytes)
  0x0000000000000005 (STRTAB)          0x3fc
  0x000000000000000a (STRSZ)           102 (bytes)
  0x000000006ffffef5 (GNU_HASH)        0x3e0
  0x0000000000000020 (PREINIT_ARRAY)   0x2660
  0x0000000000000021 (PREINIT_ARRAYSZ) 16 (bytes)
  0x0000000000000019 (INIT_ARRAY)      0x2670
  0x000000000000001b (INIT_ARRAYSZ)    16 (bytes)
  0x000000000000001a (FINI_ARRAY)      0x2680
  0x000000000000001c (FINI_ARRAYSZ)    16 (bytes)
  0x000000006ffffff0 (VERSYM)          0x3b8
  0x000000006ffffffe (VERNEED)         0x3c0
  0x000000006fffffff (VERNEEDNUM)      1
  0x0000000000000000 (NULL)            0x0

File: lib
Dynamic section at offset 0x618 contains 24 entries:
  Tag                Type           Name/Value
  0x000000000000001d (RUNPATH)      Library runpath: [/data/data/com.termux/files/usr/lib]
  0x0000000000000001 (NEEDED)       Shared library: [libdl.so]
  0x0000000000000001 (NEEDED)       Shared library: [libc.so]
  0x000000000000001e (FLAGS)        BIND_NOW
  0x000000006ffffffb (FLAGS_1)      NOW
  0x0000000000000007 (RELA)         0x3e0
  0x0000000000000008 (RELASZ)       72 (bytes)
  0x0000000000000009 (RELAENT)      24 (bytes)
  0x000000006ffffff9 (RELACOUNT)    3
  0x0000000000000017 (JMPREL)       0x428
  0x0000000000000002 (PLTRELSZ)     72 (bytes)
  0x0000000000000003 (PLTGOT)       0x2798
  0x0000000000000014 (PLTREL)       RELA
  0x0000000000000006 (SYMTAB)       0x2d0
  0x000000000000000b (SYMENT)       24 (bytes)
  0x0000000000000005 (STRTAB)       0x374
  0x000000000000000a (STRSZ)        105 (bytes)
  0x000000006ffffef5 (GNU_HASH)     0x358
  0x000000000000001a (FINI_ARRAY)   0x2608
  0x000000000000001c (FINI_ARRAYSZ) 16 (bytes)
  0x000000006ffffff0 (VERSYM)       0x330
  0x000000006ffffffe (VERNEED)      0x338
  0x000000006fffffff (VERNEEDNUM)   1
  0x0000000000000000 (NULL)         0x0

~ $ ./test_dlopen ./exe
Yes its running
Trying to access ./exe
linker: "/data/data/com.termux/files/home/exe": ignoring DT_PREINIT_ARRAY in shared library!
Access ok
~ $ ./test_dlopen ./lib
Yes its running
Trying to access ./lib
Access ok

It is possible to reproduce with our packages as well, but unlikely to happen due to:

Our packages are well defined (exe in bin dir, so in lib dir, no mixing exe and so in lib dir AFAICT)
Proper usage of dlopen() on libs (NOT executables) by the packages

~ $ ./test_dlopen $PREFIX/bin/clang
Yes its running
Trying to access /data/data/com.termux/files/usr/bin/clang
linker: "/data/data/com.termux/files/usr/bin/clang-16": ignoring DT_PREINIT_ARRAY in shared library!
Access ok
~ $ ./test_dlopen $PREFIX/lib/libclang.so
Yes its running
Trying to access /data/data/com.termux/files/usr/lib/libclang.so
Access ok

Suggest to change PR #21 into opt-in since the compilers are working correctly.
For the harmless warning, I am leaning towards improper usage by end users. This is usually the case when APK packs lib*.so not just for libraries but also executables...

Strip DT_PREINIT_ARRAY for PIE? #16

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