[lldb] Enforce that only the LLDB API unit tests can link liblldb (#162384)

Enforce that only specific tests can link liblldb. All the other unit
tests statically link the private libraries. Linking both the static
libraries and liblldb results in duplicated symbols.

Fixes #162378

Author: JDevlieghere

lldb/unittests/API/CMakeLists.txt

@@ -3,6 +3,8 @@ add_lldb_unittest(APITests
   SBLineEntryTest.cpp
   SBMutexTest.cpp
 
+  SBAPITEST
+
   LINK_LIBS
     liblldb
   )

lldb/unittests/CMakeLists.txt

@@ -12,7 +12,7 @@ endif()
 
 function(add_lldb_unittest test_name)
   cmake_parse_arguments(ARG
-    ""
+    "SBAPITEST"
     ""
     "LINK_LIBS;LINK_COMPONENTS"
     ${ARGN})
@@ -21,6 +21,10 @@ function(add_lldb_unittest test_name)
     message(FATAL_ERROR "Unit test name must end with 'Tests' for lit to find it.")
   endif()
 
+  if ("liblldb" IN_LIST ARG_LINK_LIBS AND NOT ARG_SBAPITEST)
+    message(FATAL_ERROR "The ${test_name} are not allowed to link liblldb.")
+  endif()
+
   list(APPEND LLVM_LINK_COMPONENTS ${ARG_LINK_COMPONENTS})
 
   add_unittest(LLDBUnitTests

lldb/unittests/DAP/CMakeLists.txt

@@ -12,6 +12,8 @@ add_lldb_unittest(DAPTests
   TestBase.cpp
   VariablesTest.cpp
 
+  SBAPITEST
+
   LINK_COMPONENTS
     Support
   LINK_LIBS