Test program fails to compile with strict-aliasing errors

[eli-schwartz]

FAILED: src/test/CMakeFiles/test-z3.dir/hwf.cpp.o 
/usr/bin/x86_64-pc-linux-gnu-g++ -D_EXTERNAL_RELEASE -D_MP_INTERNAL -I/var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5_build-abi_x86_64.amd64/src -I/var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5/src  -march=native -fstack-protector-all -O2 -pipe -fdiagnostics-color=always -frecord-gcc-switches -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 -fstack-clash-protection -flto=4 -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing  -Wformat -Werror=format-security -Werror=odr  -Werror=return-type  -std=gnu++17 -mfpmath=sse -msse -msse2 -Wall -MD -MT src/test/CMakeFiles/test-z3.dir/hwf.cpp.o -MF src/test/CMakeFiles/test-z3.dir/hwf.cpp.o.d -o src/test/CMakeFiles/test-z3.dir/hwf.cpp.o -c /var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5/src/test/hwf.cpp
/var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5/src/test/hwf.cpp: In function ‘void bug_is_int()’:
/var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5/src/test/hwf.cpp:106:21: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
  106 |     double   val = *(double*)(raw_val);
      |                     ^~~~~~~~~~~~~~~~~~
/var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5/src/test/hwf.cpp:106:14: warning: ‘raw_val’ is used uninitialized [-Wuninitialized]
  106 |     double   val = *(double*)(raw_val);
      |              ^~~
/var/tmp/portage/sci-mathematics/z3-4.12.5/work/z3-z3-4.12.5/src/test/hwf.cpp:105:14: note: ‘raw_val’ declared here
  105 |     unsigned raw_val[2] = { 2147483648u, 1077720461u };
      |              ^~~~~~~
cc1plus: some warnings being treated as errors

Downstream bug report: https://bugs.gentoo.org/879327
Full build log: build.log