forked from OSchip/llvm-project
9877f689f2
This patch introduces some magic in tablegen to create a "Pedantic" diagnostic group which automagically includes all warnings that are extensions. This allows a user to suppress specific warnings traditionally under -pedantic used an ordinary warning flag. This also allows users to use #pragma to silence specific -pedantic warnings, or promote them to errors, within blocks of text (just like any other warning). -Wpedantic is NOT an alias for -pedantic. Instead, it provides another way to (a) activate -pedantic warnings and (b) disable them. Where they differ is that -pedantic changes the behavior of the preprocessor slightly, whereas -Wpedantic does not (it just turns on the warnings). The magic in the tablegen diagnostic emitter has to do with computing the minimal set of diagnostic groups and diagnostics that should go into -Wpedantic, as those diagnostics that already members of groups that themselves are (transitively) members of -Wpedantic do not need to be included in the Pedantic group directly. I went back and forth on whether or not to magically generate this group, and the invariant was that we always wanted extension warnings to be included in -Wpedantic "some how", but the bookkeeping would be very onerous to manage by hand. -no-pedantic (and --no-pedantic) is included for completeness, and matches many of the same kind of flags the compiler already supports. It does what it says: cancels out -pedantic. One discrepancy is that if one specifies --no-pedantic and -Weverything or -Wpedantic the pedantic warnings are still enabled (essentially the -W flags win). We can debate the correct behavior here. Along the way, this patch nukes some code in TextDiagnosticPrinter.cpp and CXStoredDiagnostic.cpp that determine whether to include the "-pedantic" flag in the warning output. This is no longer needed, as all extensions now have a -W flag. This patch also significantly reduces the number of warnings not under flags from 229 to 158 (all extension warnings). That's a 31% reduction. llvm-svn: 159875 |
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| clang | ||
| compiler-rt | ||
| debuginfo-tests | ||
| libclc | ||
| libcxx | ||
| libcxxabi | ||
| lld | ||
| lldb | ||
| llvm | ||
| polly | ||