This is not longer being updated. For current packages see the Fedora-clang results. -------------------------------------------- Tests with LLVM clang 15.0.1, other details as for fedora-clang at https://www.stats.ox.ac.uk/pub/bdr/Rconfig/r-devel-linux-x86_64-fedora-clang Release notes for clang 15.0.0 can be found at https://releases.llvm.org/15.0.0/tools/clang/docs/ReleaseNotes.html Note in particular The -Wimplicit-function-declaration warning diagnostic now defaults to an error in C99 and later. Prior to C2x, it may be downgraded to a warning with -Wno-error=implicit-function-declaration, or disabled entirely with -Wno-implicit-function-declaration. As of C2x, support for implicit function declarations has been removed, and the warning options will have no effect. although that seems to have bee temprorily rolled back for 15.0.1. Modified the behavior of -Wstrict-prototypes and added a new, related diagnostic -Wdeprecated-non-prototype. The strict prototypes warning will now only diagnose deprecated declarations and definitions of functions without a prototype where the behavior in C2x will remain correct. This diagnostic remains off by default but is now enabled via -pedantic due to it being a deprecation warning. -Wstrict-prototypes has no effect in C2x or when -fno-knr-functions is enabled. -Wdeprecated-non-prototype will diagnose cases where the deprecated declarations or definitions of a function without a prototype will change behavior in C2x. Additionally, it will diagnose calls which pass arguments to a function without a prototype. This warning is enabled only when the -Wdeprecated-non-prototype option is enabled at the function declaration site, which allows a developer to disable the diagnostic for all callers at the point of declaration. This diagnostic is grouped under the -Wstrict-prototypes warning group, but is enabled by default. -Wdeprecated-non-prototype has no effect in C2x or when -fno-knr-functions is enabled. Recent fedora-clang check runs report as WARNINGs the following compiler warnings: -Wunneeded-internal-declaration (new in clang 15) -Winvalid-utf8 (new in clang 15) -Wformat (also seen in Apple clang 14 and gcc's -Wformat= is similar) -Wsizeof-pointer-div (also in Apple clang and gcc) -Wliteral-conversion (also Apple clang) -Wempty-body (also Apple clang) -Wreturn-stack-address (also Apple clang) -Wnon-c-typedef-for-linkage (also Apple clang) -Wc++??-extensions (also Apple clang and LLVM clang-14) -Wc++??-attribute-extensions (for C++14, 17, 20 and 2b) -Wstrict-prototypes and -Wdeprecated-non-prototype are reported in the fedoara-clang results, but only as a 'clang15' additional issue if not also reported (as -Wstrict-prototypes) by gcc12.