Qt5-5.8.0 - Pointer to incomplete class type is not allowed

[vanzod]

Building Qt5-5.8.0-intel-2017b on a system with OpenSSL 1.1.0f fails with the following error:

icpc -c -pch-use .pch/Qt5Network.pchi -include ../corelib/global/qt_pch.h -O2 -falign-functions=16 -ansi-alias -fstrict-aliasing -std=c++1y -fvisibility=hidden -fvisibility-inlines-hidden -w1 -Wall -Wcheck -wd1572,873,2259,2261,3373 -D_REENTRANT -D_REENTRANT -D_REENTRANT -fPIC -DQT_NO_USING_NAMESPACE -DQT_NO_FOREACH -DQT_USE_SYSTEM_PROXIES -DQT_BUILD_NETWORK_LIB -DQT_BUILDING_QT -DQT_NO_CAST_TO_ASCII -DQT_ASCII_CAST_WARNINGS -DQT_MOC_COMPAT -DQT_USE_QSTRINGBUILDER -DQT_DEPRECATED_WARNINGS -DQT_DISABLE_DEPRECATED_BEFORE=0x050000 -DQT_NO_EXCEPTIONS -D_LARGEFILE64_SOURCE -D_LARGEFILE_SOURCE -DQT_NO_DEBUG -DQT_CORE_LIB -I. -Ikernel -I../../include -I../../include/QtNetwork -I../../include/QtNetwork/5.8.0 -I../../include/QtNetwork/5.8.0/QtNetwork -I../../include/QtCore/5.8.0 -I../../include/QtCore/5.8.0/QtCore -I../../include/QtCore -I.moc -I../../mkspecs/linux-icc-64 -o .obj/qsslcertificate_openssl.o ssl/qsslcertificate_openssl.cpp
"ssl/qsslcertificate_openssl.cpp": using precompiled header file ".pch/Qt5Network.pchi"
ssl/qsslcertificate_openssl.cpp(69): error: pointer to incomplete class type is not allowed
          return qHashBits(x509->sha1_hash, SHA_DIGEST_LENGTH, seed);
                           ^

ssl/qsslcertificate_openssl.cpp(93): error: pointer to incomplete class type is not allowed
              QByteArray::number(qlonglong(q_ASN1_INTEGER_get(d->x509->cert_info->version)) + 1);
                                                              ^

ssl/qsslcertificate_openssl.cpp(102): error: pointer to incomplete class type is not allowed
          ASN1_INTEGER *serialNumber = d->x509->cert_info->serialNumber;
                                       ^

ssl/qsslcertificate_openssl.cpp(238): error: pointer to incomplete class type is not allowed
      X509_PUBKEY *xkey = d->x509->cert_info->key;
                          ^

ssl/qsslcertificate_openssl.cpp(242): error: pointer to incomplete class type is not allowed
      if (q_EVP_PKEY_type(pkey->type) == EVP_PKEY_RSA) {
                          ^

ssl/qsslcertificate_openssl.cpp(246): error: pointer to incomplete class type is not allowed
      } else if (q_EVP_PKEY_type(pkey->type) == EVP_PKEY_DSA) {
                                 ^

ssl/qsslcertificate_openssl.cpp(251): error: pointer to incomplete class type is not allowed
      } else if (q_EVP_PKEY_type(pkey->type) == EVP_PKEY_EC) {
                                 ^

ssl/qsslcertificate_openssl.cpp(256): error: pointer to incomplete class type is not allowed
      } else if (q_EVP_PKEY_type(pkey->type) == EVP_PKEY_DH) {
                                 ^

compilation aborted for ssl/qsslcertificate_openssl.cpp (code 2)

[boegel]

@vanzod Same problem as
#6644?

Also relevant:
#6759

[vanzod]

@boegel The root cause is the same: OpenSSL 1.1 not being backward compatible. Here are a couple of Qt bug reports regarding this issue:
https://bugreports.qt.io/browse/QTBUG-52905
https://bugreports.qt.io/browse/QTBUG-51553

There is no official patch for version 5.8.0, but OpenSSL 1.1 is fully supported from Qt 5.10.
In the meantime the workaround on Debian is to install libssl1.0-dev and skip OS dependency checks. Not a clean solution but it puts me back on track.

[boegel]

@vanzod In the long run, we can reconsider our current approach to OpenSSL, and let EasyBuild install it as a dependency rather than relying on the OS.

The support we now have for module wrappers makes this feasible, but of course it'll be important that we're on top of things w.r.t. security updates (and maybe we should make it opt-in)...

[Micket]

I think this is no longer an issue with more uptodate qt5's, and our OpenSSL wrapper is good like it is i think. Closing.