The header parameter disables the creation of fake prototypes, and CheckFunc always calls the function with no arguments, so the check fails. This presently works by accident because compilers ignore the second #include in '#include <sys/types.h>#include <sys/xattr.h>' (so no prototype gets declared) and supply an implicit function declaration which allows calls with any number of arguments.
The header parameter disables the creation of fake prototypes, and CheckFunc always calls the function with no arguments, so the check fails. This presently works by accident because compilers ignore the second #include in '#include <sys/types.h>#include <sys/xattr.h>' (so no prototype gets declared) and supply an implicit function declaration which allows calls with any number of arguments.
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