Regression in [0] which caused `execinfo.h` not to be detected by CMake.
Setting a default variable for other platforms prevented the new
variable from being set.
[0]: f197b1a1f1
Regression in [0] which caused `execinfo.h` not to be detected by CMake.
Setting a default variable for other platforms prevented the new
variable from being set.
[0]: f197b1a1f1