Warnings

[renzenicolai]

	add_compile_options(
		# General
		-Wall												# Enable warnings for common coding mistakes or potential errors.
		-Wextra												# Extensions for -Wall.
		$<$<BOOL:${WARNING_AS_ERROR}>:-Werror>				# Treat warnings as errors to fail the build in case of warnings.
		-Wpedantic											# Warn for now standard C++.
		$<$<COMPILE_LANGUAGE:C>:-Werror=implicit-function-declaration> # Calling functions that don't exist are errors
		$<$<COMPILE_LANGUAGE:C>:-Werror=incompatible-pointer-types>
		$<$<COMPILE_LANGUAGE:C>:-Werror=int-conversion>
		# Type conversion
		-Wconversion										# Warn about implicit type conversions which (may) change the value.
		-Wsign-conversion									# Warn about implicit sign conversions.
		-Wdouble-promotion									# Warn about floats being implictly converted to doubles.
		-Wfloat-equal										# Warn about floatint point values used in equality tests.
		-Wpointer-arith										# Warn when sizeof(void) is used (directly or indirectly).
		# -Wcast-qual											# Warn when casting removes a type qualifier from a pointer.
		-Wcast-align										# Warn when casting a pointers changes the alignment of the pointee.
		$<$<COMPILE_LANGUAGE:C>:-Wbad-function-cast>		# Warn about casts to function pointers.
		-Wstrict-overflow=2									# Warn about optimizations where signed overflow is assumed not to occour.
		# Misc
		-Wshadow											# Warn about duplicated variable names.
		# -Wswitch-enum										# Warn about switch statements not using all possible enum values.
		-Wimplicit-fallthrough								# Warn about implicit, un-annotated, fallthroughs.
		-Wnull-dereference									# Warn about possible null pointer dereference code paths.
		-Wundef												# Warn when undefined macros are used (implicit conversion to 0.)
		$<$<COMPILE_LANGUAGE:C>:-Wstrict-prototypes>		# Warn when a function declaration misses argument types.
		-Wunused											# Warn about any unused parameter/function/variable/etc...
		-Wmisleading-indentation							# Warn about indentation giving the impression of scope.
		-Winline											# Warn when desired inlining is not possible.
		# Strings related
		-Wvla												# Warn about variable-length arrays being used.
		-Wwrite-strings										# Warn when attempting to write to a string constant.
		-Wformat=2											# Verify printf/scanf/.. arguments and format strings match.
		# Code generation
		-fno-common													# Warn when global variables are not unique (and unintentionaly merged.)
		-fstack-usage												# Generate stack depth information.
		-fvisibility=hidden											# Sets the default symbol visibility to hidden.
		-fwrapv														# Assume signed arithmatic may wrap around.
		-ftrivial-auto-var-init=zero								# Ensure automatic variables are always initialized.
	)

Would be nice to solve some of the issues pointed out when compiling with these extra warnings enabled 😄