Compiler warnings are a tool we enable as developers to detect
issues with our source code that go beyond the basic requirements
of compiling C++ code. For example, many implicit conversions are
perfectly correct, and defined behavior in C++ but we choose to
disallow them with -Wconversion. This is something only us devs
have to care about. Someone using SFML wants the library to work
well but does not need to concern themselves with such low level
details about its implementation.
By disabling warnings in non-developer builds, we ensure that non-
developer users of SFML are not going to see console noise due to
warnings and it prevents issues like GCC's bug 82952 which causes
compilation to halt indefitely due to a bug in how a compiler
warning is implemented.
This also improves compatibility with older compilers. If we enable
warnings in all builds no matter what, we have to protect against
compilers we don't expect. Perhaps someone uses an older version
of GCC that we haven't tested with. This compiler is perfectly fine
compiling our C++ but we happen to use a warning flag it does not
recognize so the build fails. This is not a good reason for a
build to fail but nevertheless it's something we have to deal with
so long as we always enable warnings.
SFML_WARNINGS_AS_ERRORS is now named somewhat incorrectly but I
retained the name for compatibility's sake. We can rename it to
SFML_ENABLE_WARNINGS or something similar in SFML 4.
This is what it currently looks like when find_package(SFML) fails
due to locating the incorrect library type:
CMake Error at <path>/<to>/lib/cmake/SFML/SFMLConfig.cmake:182 (message):
Requested SFML configuration (Shared) was not found
Call Stack (most recent call first):
CMakeLists.txt:7 (find_package)
CMake Error at CMakeLists.txt:7 (find_package):
Found package configuration file:
<path>/<to>/lib/cmake/SFML/SFMLConfig.cmake
but it set SFML_FOUND to FALSE so package "SFML" is considered to be NOT
FOUND.
After this change the "Requested SFML configuration" line is followed by either
Set SFML_STATIC_LIBRARIES to ON for static libraries
or
Set SFML_STATIC_LIBRARIES to OFF for shared libraries
depending on the value of SFML_STATIC_LIBRARIES. This should help clear up a
common source of confusion when users build SFML from source. The library
follows CMake convention of building static libraries by default but our
config module assumes shared libraries by default so those who build SFML
from source are prone to run into this error.
