Add few docs and implementation of strcpy and strcat.

Summary:
This patch illustrates some of the features like modularity we want
in the new libc. Few other ideas like different kinds of testing, redirectors
etc are not yet present.

Reviewers: dlj, hfinkel, theraven, jfb, alexshap, jdoerfert

Subscribers: mgorny, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67867

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@373764 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -59,7 +59,7 @@ endif()
 # LLVM_EXTERNAL_${project}_SOURCE_DIR using LLVM_ALL_PROJECTS
 # This allows an easy way of setting up a build directory for llvm and another
 # one for llvm+clang+... using the same sources.
-set(LLVM_ALL_PROJECTS "clang;clang-tools-extra;compiler-rt;debuginfo-tests;libclc;libcxx;libcxxabi;libunwind;lld;lldb;llgo;openmp;parallel-libs;polly;pstl")
+set(LLVM_ALL_PROJECTS "clang;clang-tools-extra;compiler-rt;debuginfo-tests;libc;libclc;libcxx;libcxxabi;libunwind;lld;lldb;llgo;openmp;parallel-libs;polly;pstl")
 set(LLVM_ENABLE_PROJECTS "" CACHE STRING
 	"Semicolon-separated list of projects to build (${LLVM_ALL_PROJECTS}), or \"all\".")
 if( LLVM_ENABLE_PROJECTS STREQUAL "all" )

projects/CMakeLists.txt

@@ -31,6 +31,7 @@ if(${LLVM_BUILD_RUNTIME})
     # dependent projects can see the target names of their dependencies.
     add_llvm_external_project(libunwind)
     add_llvm_external_project(pstl)
+    add_llvm_external_project(libc)
     add_llvm_external_project(libcxxabi)
     add_llvm_external_project(libcxx)
   endif()