Put static local variables of inline functions in the function comdat.

The variable (and the GV) is only ever used if the function is. Putting it
in the function's comdat make it easier for the linker to discard them.

The motivating example is

struct S {
  static const int x;
};
// const int S::x = 42;
inline const int *f() {
  static const int y = S::x;
  return &y;
}
const int *g() { return f(); }

With S::x commented out, _ZZ1fvE1y is a variable with a guard variable
that is initialized by f.

With S::x present, _ZZ1fvE1y is a constant.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@224369 91177308-0d34-0410-b5e6-96231b3b80d8
Move -Wkeyword-macro into -pedantic, remove -Wreserved-id-macro.

As discussed on the post-commit review thread for r224012, -Wkeyword-macro fires
mostly on headers trying to set up portable defines and doesn't find much bad
stuff in practice.  But [macro.names]p2 does disallow defining or undefining
keywords, override and final, and alignas, so keep the warning but move it
into -pedantic.

-Wreserved-id-macro warns on

    #define __need_size_t

which is more or less public api for glibc headers. Since this warning isn't
motivated by a standard, remove it.

(See also r223114 for a previous follow-up to r224012.)


git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@224371 91177308-0d34-0410-b5e6-96231b3b80d8
Add a new flag, -fspell-checking-limit=<number> to control how many times we'll do spell checking. Note that spell checking will change the produced AST, so we don't automatically change this value when someone sets -ferror-limit=. With this, merge test typo-correction-pt2.cpp into typo-correction.cpp.

Remove Sema::UnqualifiedTyposCorrected, a cache of corrected typos. It would only cache typo corrections that didn't provide ValidateCandidate of which there were few left, and it had a bug when we had the same identifier spelled wrong twice. See the last two tests in typo-correction.cpp for cases this fires.


git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@224375 91177308-0d34-0410-b5e6-96231b3b80d8
Fix typo in comment. NFC.


git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@224377 91177308-0d34-0410-b5e6-96231b3b80d8
Fix handling of invalid -O options.

We were checking the value after truncating it to a bitfield.

Thanks to Yunzhong Gao for noticing it.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@224378 91177308-0d34-0410-b5e6-96231b3b80d8