Build fails due to warnings turned into errors by passing -Werror

[glaubitz]

The build currently fails with gcc-8 on openSUSE Tumbleweed with:

[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c: In function 'encode_float_value':
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c:3132:34: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
[   34s]      uint32_t value_as_uint32 = *((uint32_t*)(void*)&value);
[   34s]                                  ~^~~~~~~~~~~~~~~~~~~~~~~~~
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c: In function 'encode_double_value':
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c:3196:34: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
[   34s]      uint64_t value_as_uint64 = *((uint64_t*)(void*)&value);
[   34s]                                  ~^~~~~~~~~~~~~~~~~~~~~~~~~
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c: In function 'internal_decoder_decode_bytes':
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c:5226:23: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
[   34s]                      *((uint32_t*)&internal_decoder_data->decode_to_value->value.float_value) = 0;
[   34s]                       ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c:5239:23: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
[   34s]                      *((uint64_t*)&internal_decoder_data->decode_to_value->value.double_value) = 0;
[   34s]                       ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c:5723:23: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
[   34s]                      *((uint32_t*)&internal_decoder_data->decode_to_value->value.float_value) += ((uint32_t)buffer[0]) << ((3 - internal_decoder_data->bytes_decoded) * 8);
[   34s]                       ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[   34s] /home/abuild/rpmbuild/BUILD/uamqp-1.1.0/src/vendor/azure-uamqp-c/src/amqpvalue.c:5745:23: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
[   34s]                      *((uint64_t*)&internal_decoder_data->decode_to_value->value.double_value) += ((uint64_t)buffer[0]) << ((7 - internal_decoder_data->bytes_decoded) * 8);
[   34s]                       ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[   36s] cc1: all warnings being treated as errors
[   36s] gmake[2]: *** [CMakeFiles/uamqp.dir/build.make:102: CMakeFiles/uamqp.dir/src/amqpvalue.c.o] Error 1
[   36s] gmake[1]: *** [CMakeFiles/Makefile2:73: CMakeFiles/uamqp.dir/all] Error 2
[   36s] gmake: *** [Makefile:141: all] Error 2

This is because multiple cmake files pass -Werror to the compiler:

glaubitz@suse-laptop:~/suse/home:glaubitz:branches:devel:languages:python:azure3/python-uamqp> grep -R Werror *
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/configs/azure_iot_build_rules.cmake:    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/configs/azure_iot_build_rules.cmake:    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/configs/azure_iot_build_rules.cmake:    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/configs/azure_iot_build_rules.cmake:    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/umock-c/CMakeLists.txt:# Build with -Werror
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/umock-c/CMakeLists.txt:    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/umock-c/CMakeLists.txt:    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/umock-c/deps/ctest/CMakeLists.txt:    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/umock-c/deps/ctest/CMakeLists.txt:    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/ctest/CMakeLists.txt:    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
uamqp-1.1.0/src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/ctest/CMakeLists.txt:    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
glaubitz@suse-laptop:~/suse/home:glaubitz:branches:devel:languages:python:azure3/python-uamqp>

At the time, gcc generates warnings for the code. Thus, in order to fix this, either drop -Werror from the C/CXXFLAGS or fix the warnings.

[thatch]

I'm seeing this as well.

[thatch]

Looks like -Werror is coming from one of the cmake files, I dropped the lines that reference it from these three files and have a successful build:

src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/ctest/CMakeLists.txt
src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/testtools/umock-c/CMakeLists.txt
src/vendor/azure-uamqp-c/deps/azure-c-shared-utility/configs/azure_iot_build_rules.cmake