C/C++/ObjC language server supporting cross references, hierarchies, completion and semantic highlighting
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MaskRay completion: if preamble size changes, rebuild it
Fix #190

If a new header is added, the preamble size changes. Language clients may cache completion results, thus we rebuild preamble to avoid inaccurate results.
Latest commit 7a79ed9 Jan 13, 2019



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ccls, which originates from cquery, is a C/C++/Objective-C language server.

It has a global view of the code base and support a lot of cross reference features, see wiki/FAQ. It starts indexing the whole project (including subprojects if exist) parallelly when you open the first file, while the main thread can serve requests before the indexing is complete. Saving files will incrementally update the index.

Compared with cquery, it makes use of C++17 features, has less third-party dependencies and slimmed-down code base. It leverages Clang C++ API as clangd does, which provides better support for code completion and diagnostics. Refactoring is a non-goal as it can be provided by clang-include-fixer and other Clang based tools.

The comparison with cquery as noted on 2018-07-15:

cquery ccls
third_party more fewer
C++ C++14 C++17
clang API libclang (C) clang/llvm C++
Filesystem AbsolutePath + custom routines llvm/Support
index libclang clangIndex, some enhancement
pipeline index merge+id remapping simpler and more robust

cquery has system include path detection (through running the compiler driver) while ccls uses clangDriver.

>>> Getting started (CLICK HERE) <<<

ccls can index itself (~180MiB RSS when idle, noted on 2018-09-01), FreeBSD, glibc, Linux, LLVM (~1800MiB RSS), musl (~60MiB RSS), ... with decent memory footprint. See wiki/compile_commands.json for examples.