[lldb/CMake] Don't use return() from macro()

> A macro is executed as if the macro body were pasted in place of the
> calling statement. This has the consequence that a return() in a macro
> body does not just terminate execution of the macro

After converting from a function() to a macro(), the return() became
invalid. This modifies the control flow to elude the return.

1 files changed, 7 insertions, 4 deletions

diff --git a/lldb/cmake/modules/LLDBConfig.cmake b/lldb/cmake/modules/LLDBConfig.cmake
index 3fc466b8f35..c34ef76cb65 100644
--- a/lldb/cmake/modules/LLDBConfig.cmake
+++ b/lldb/cmake/modules/LLDBConfig.cmake
@@ -29,16 +29,19 @@ macro(add_optional_dependency variable description package found)
   string(TOUPPER "${${variable}}" ${variable})
 
   if("${${variable}}" STREQUAL "AUTO")
+    set(find_package TRUE)
     set(maybe_required)
   elseif(${${variable}})
+    set(find_package TRUE)
     set(maybe_required REQUIRED)
   else()
-    set(${variable} OFF PARENT_SCOPE)
-    return()
+    set(${variable} FALSE PARENT_SCOPE)
   endif()
 
-  find_package(${package} ${maybe_required})
-  set(${variable} "${${found}}")
+  if(${find_package})
+    find_package(${package} ${maybe_required})
+    set(${variable} "${${found}}")
+  endif()
 endmacro()
 
 add_optional_dependency(LLDB_ENABLE_LIBEDIT "Enable editline support." LibEdit libedit_FOUND)