[CMake] Add missing find_package for LibEdit

[ekilmer]

Summary

After building and installing LLVM with LibEdit as a dependency, it is
necessary to find it again when LLVM is consumed by another CMake
project, otherwise CMake will report an error about a missing target.

Note that the FindLibEdit.cmake file is in the "LLVM Common CMake
Utils" directory, outside of the LLVM sub-project source directory, so
the installed LLVMConfig.cmake relies on the user having installed the
LLVM common CMake modules or make available their own Find module.

Also note that the controlling HAVE_LIBEDIT CMake variable in
LLVMConfig.cmake.in has a different naming convention compared to
other similar variables like 'LLVM_ENABLE_TERMINFO'. Refactoring this
name would involve touching additional files and should be a follow-up
commit.

[ekilmer]

Rebase on 'main'. Trying to fix build

[phosek]

LGTM

[ekilmer]

Thank you for the review @phosek!

I don't believe I have the ability to commit this change, as this is my first contribution to LLVM. Any help in committing this would be appreciated. Thank you.

[ekilmer]

Ping @phosek. Is there anything else that needs to be done on my end before landing this on main branch?

[ekilmer]

Ping. How do I get this committed to main branch?

[phosek]

In D147153#4281193, @ekilmer wrote:

Ping. How do I get this committed to main branch?

I have landed the change in rG7d89e6c1c0a01c959beddab643e39d2bc4c2c97d.

llvm/cmake/config-ix.cmake

 
 # Don't look for these libraries if we're using MSan, since uninstrumented third
 # party code may call MSan interceptors like strlen, leading to false positives.
 if(NOT LLVM_USE_SANITIZER MATCHES "Memory.*")
   # Don't look for these libraries on Windows.
   if (NOT PURE_WINDOWS)
     # Skip libedit if using ASan as it contains memory leaks.
     if (LLVM_ENABLE_LIBEDIT AND NOT LLVM_USE_SANITIZER MATCHES ".*Address.*")
+      if(LLVM_ENABLE_LIBEDIT STREQUAL FORCE_ON)
+        find_package(LibEdit REQUIRED)
+      else()
         find_package(LibEdit)
-      set(HAVE_LIBEDIT ${LibEdit_FOUND})
+      endif()
+      set(HAVE_LIBEDIT "${LibEdit_FOUND}")
     else()
       set(HAVE_LIBEDIT 0)
     endif()
     if(LLVM_ENABLE_TERMINFO)
       if(LLVM_ENABLE_TERMINFO STREQUAL FORCE_ON)
         find_package(Terminfo REQUIRED)
       else()
         find_package(Terminfo)
       endif()
       set(LLVM_ENABLE_TERMINFO "${Terminfo_FOUND}")
     endif()
   else()
+    set(HAVE_LIBEDIT 0)
     set(LLVM_ENABLE_TERMINFO 0)
   endif()
 else()
+  set(HAVE_LIBEDIT 0)
   set(LLVM_ENABLE_TERMINFO 0)
 endif()
 
 check_library_exists(xar xar_open "" LLVM_HAVE_LIBXAR)
 if(LLVM_HAVE_LIBXAR)
   message(STATUS "The xar file format has been deprecated: LLVM_HAVE_LIBXAR might be removed in the future.")
   # The xar file format has been deprecated since macOS 12.0.
   if (CMAKE_OSX_DEPLOYMENT_TARGET VERSION_GREATER_EQUAL 12)

llvm/cmake/modules/LLVMConfig.cmake.in

 
 set(LLVM_ENABLE_FFI @LLVM_ENABLE_FFI@)
 if(LLVM_ENABLE_FFI)
   find_package(FFI)
 endif()
 
 set(LLVM_ENABLE_RTTI @LLVM_ENABLE_RTTI@)
 
+set(LLVM_ENABLE_LIBEDIT @HAVE_LIBEDIT@)
+if(LLVM_ENABLE_LIBEDIT)
+  find_package(LibEdit)
+endif()
+
 set(LLVM_ENABLE_TERMINFO @LLVM_ENABLE_TERMINFO@)
 if(LLVM_ENABLE_TERMINFO)
   find_package(Terminfo)
 endif()
 
 set(LLVM_ENABLE_THREADS @LLVM_ENABLE_THREADS@)
 
 set(LLVM_ENABLE_UNWIND_TABLES @LLVM_ENABLE_UNWIND_TABLES@)