diff --git a/crypto/asn1/a_verify.c b/crypto/asn1/a_verify.c
index 376b359..1d42c2c 100644
--- a/crypto/asn1/a_verify.c
+++ b/crypto/asn1/a_verify.c
@@ -7,9 +7,6 @@
  * https://www.openssl.org/source/license.html
  */
 
-/* for secure_getenv */
-#define _GNU_SOURCE
-
 #include <stdio.h>
 #include <time.h>
 #include <sys/types.h>
@@ -130,7 +127,7 @@ int ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *a,
             goto err;
         ret = -1;
     } else if ((mdnid == NID_md5
-               && secure_getenv("OPENSSL_ENABLE_MD5_VERIFY") == NULL) ||
+               && getenv("OPENSSL_ENABLE_MD5_VERIFY") == NULL) ||
                mdnid == NID_md4 || mdnid == NID_md2 || mdnid == NID_sha) {
         ASN1err(ASN1_F_ASN1_ITEM_VERIFY,
                 ASN1_R_UNKNOWN_MESSAGE_DIGEST_ALGORITHM);