[clangd] GlobalCompilationDatabase interface changes

Summary:
- GlobalCompilationDatabase now returns a single command (that's all we use)
- fallback flags are now part of the GlobalCompilationDatabase.
  There's a default implementation that they can optionally customize.
- this allows us to avoid invoking the fallback logic on two separate codepaths
- race on extra flags fixed by locking the mutex
- made GCD const-correct (DBGCD does have mutating methods)

Reviewers: hokein

Subscribers: klimek, cfe-commits, ilya-biryukov

Differential Revision: https://reviews.llvm.org/D40733

llvm-svn: 319647
4 files changed
tree: 70443d88e80cd80d4dbcb79359b8594775efad76
  1. clang/
  2. clang-tools-extra/
  3. compiler-rt/
  4. debuginfo-tests/
  5. libclc/
  6. libcxx/
  7. libcxxabi/
  8. libunwind/
  9. lld/
  10. lldb/
  11. llgo/
  12. llvm/
  13. openmp/
  14. parallel-libs/
  15. polly/
  16. README.md
README.md

Low Level Virtual Machine (LLVM)

This directory and its subdirectories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments.