Use aws-lc to intern symbols in s2n-tls

Author: kou

cpp/cmake_modules/ThirdpartyToolchain.cmake

@@ -1028,6 +1028,8 @@ if(CMAKE_VERSION VERSION_GREATER_EQUAL 3.28)
 endif()
 
 macro(prepare_fetchcontent)
+  # CACHE is for products that still use OLD as CMP0077 (option()
+  # honors normal variables).
   set(BUILD_SHARED_LIBS
       OFF
       CACHE BOOL "" FORCE)
@@ -5041,10 +5043,10 @@ function(build_awssdk)
   message(STATUS "Building AWS SDK for C++ from source")
 
   set(AWSSDK_PRODUCTS aws-c-common aws-checksums)
-  # s2n-tls only needed on Linux.
+  # aws-lc and s2n-tls only needed on Linux.
   # We can use LINUX with CMake 3.25 or later.
   if(UNIX AND NOT APPLE)
-    list(APPEND AWSSDK_PRODUCTS s2n-tls)
+    list(APPEND AWSSDK_PRODUCTS aws-lc s2n-tls)
   endif()
   list(APPEND
        AWSSDK_PRODUCTS
@@ -5110,6 +5112,14 @@ function(build_awssdk)
       ON
       CACHE BOOL "" FORCE)
 
+  # For s2n-tls
+  set(crypto_STATIC_LIBRARY
+      "$<TARGET_FILE:crypto>"
+      CACHE STRING "" FORCE)
+  set(S2N_INTERN_LIBCRYPTO
+      ON
+      CACHE BOOL "" FORCE)
+
   set(AWSSDK_LINK_LIBRARIES)
   foreach(AWSSDK_PRODUCT ${AWSSDK_PRODUCTS})
     fetchcontent_makeavailable(${AWSSDK_PRODUCT})