openssl: Failed to load 'legacy' provider when linking OpenSSL libraries statically on AIX

I build OpenSSL 3.0 beta1 on AIX 6.1 successfully, then I tried to write a simple program (Ref: no_fips_mode.c) to test it.

bash-4.3# uname -a
AIX vAIX61-2 1 6 00C12AB64C00

no_fips_mode.c

#include <stdio.h>
#include <stdlib.h>

#include <openssl/provider.h>
#include <openssl/evp.h>

int main()
{
    OSSL_PROVIDER *deflt;
    OSSL_PROVIDER *legacy;

    legacy = OSSL_PROVIDER_load(NULL, "legacy");
    if (legacy == NULL) {
        printf("Failed to load legacy provider\n");
        return 1;
    }

    deflt = OSSL_PROVIDER_load(NULL, "default");
    if (deflt == NULL) {
        OSSL_PROVIDER_unload(legacy);
        printf("Failed to load default provider\n");
        return 1;
    }

    EVP_MD_CTX *ctx;
    EVP_MD* md4;

    ctx = EVP_MD_CTX_new();
    //md4 = EVP_md4();
    md4 = EVP_MD_fetch(NULL, "MD4", "fips=no");

    int ok = EVP_DigestInit_ex(ctx, md4, NULL);
    if (!ok)
    {
        printf("Failed to init digest context\n");
    }
    else
    {
        printf("Succeed in init digest context\n");
    }

    EVP_MD_CTX_free(ctx);
}

When I build it with linking OpenSSL libraries dynamically, then it can work as expected, but when I tried to build it with linking OpenSSL libraries statically, then it failed to load ‘legacy’ provider, ref:

bash-4.3# gcc no_fips_mode.c -maix64 -Wl,-brtl -I/usr/share/centrifydc/include -I/usr/share/centrifydc/kerberos/include -L /usr/share/centrifydc/lib64 -lcrypto -lssl -o no_fips_mode
bash-4.3# ./no_fips_mode
Succeed in init digest context

bash-4.3# gcc no_fips_mode.c -maix64 -I/usr/share/centrifydc/include -I/usr/share/centrifydc/kerberos/include -o no_fips_mode_static_link /usr/share/centrifydc/lib64/libcrypto.a /usr/share/centrifydc/lib64/libssl.a
bash-4.3# ./no_fips_mode_static_link
Failed to load legacy provider