[tarantool-patches] [PATCH 3/3] Make libdl.so optional (for FreeBSD prior to 11.2)

[Alexander Turenko <alexander.turenko@tarantool.org>]

FreeBSD 10.4 has no libdl.so.

Fixes #3750.
---
 cmake/FindCURL.cmake | 21 +++++++++++++++++----
 src/CMakeLists.txt   |  9 ++++++++-
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/cmake/FindCURL.cmake b/cmake/FindCURL.cmake
index e2e2c6f20..e13b6cde4 100644
--- a/cmake/FindCURL.cmake
+++ b/cmake/FindCURL.cmake
@@ -24,9 +24,15 @@ else()
     set(NGHTTP2_LIB_NAME nghttp2)
 endif()
 
-# Curl may require nghttp library, search for it and add to dependicies if
-# found
+# Always links pthread and dl dynamically.
+set(PTHREAD_LIB_NAME pthread)
+set(DL_LIB_NAME dl)
+
+# Curl may be linked with optional or target-dependent libraries,
+# search for them and add to dependicies if found.
 find_library(NGHTTP2_LIBRARY NAMES ${NGHTTP2_LIB_NAME})
+find_library(PTHREAD_LIBRARY NAMES ${PTHREAD_LIB_NAME})
+find_library(DL_LIBRARY NAMES ${DL_LIB_NAME})
 
 if(DEFINED CURL_ROOT)
     set(CURL_FIND_OPTS NO_CMAKE NO_CMAKE_SYSTEM_PATH)
@@ -79,14 +85,21 @@ FIND_PACKAGE_HANDLE_STANDARD_ARGS(CURL
 
 if(CURL_FOUND)
   set(CURL_LIBRARIES ${CURL_LIBRARY})
+  set(CURL_LIBRARIES ${CURL_LIBRARIES} ${OPENSSL_LIBRARIES})
   if(BUILD_STATIC)
-    # in case of a static build we have to add curl dependencies
+    # In case of a static build we have to add curl dependencies.
     if(NOT "${NGHTTP2_LIBRARY}" STREQUAL "NGHTTP2_LIBRARY-NOTFOUND")
       set(CURL_LIBRARIES ${CURL_LIBRARIES} ${NGHTTP2_LIBRARY})
     endif()
+    if(NOT "${PTHREAD_LIBRARY}" STREQUAL "PTHREAD_LIBRARY-NOTFOUND")
+      set(CURL_LIBRARIES ${CURL_LIBRARIES} ${PTHREAD_LIBRARY})
+    endif()
+    if(NOT "${DL_LIBRARY}" STREQUAL "DL_LIBRARY-NOTFOUND")
+      set(CURL_LIBRARIES ${CURL_LIBRARIES} ${DL_LIBRARY})
+    endif()
   endif()
   set(CURL_INCLUDE_DIRS ${CURL_INCLUDE_DIR})
-  set(CMAKE_REQUIRED_LIBRARIES ${CURL_LIBRARIES} ${OPENSSL_LIBRARIES} pthread dl)
+  set(CMAKE_REQUIRED_LIBRARIES ${CURL_LIBRARIES})
   set(CMAKE_REQUIRED_INCLUDES ${CURL_INCLUDE_DIRS})
   check_c_source_runs("
     #include <curl/curl.h>
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index d296348a3..ceff96ec0 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -67,7 +67,14 @@ add_custom_target(ragel
     WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
     COMMAND ragel -G2 src/uri.rl -o src/uri.c)
 
-set (generic_libraries pthread dl)
+# There is no libdl.so on FreeBSD prior to 11.2.
+#
+# Always links pthread and dl dynamically.
+set(generic_libraries pthread)
+find_library(DL_LIBRARY NAMES dl)
+if(NOT "${DL_LIBRARY}" STREQUAL "DL_LIBRARY-NOTFOUND")
+    set(generic_libraries ${generic_libraries} dl)
+endif()
 
 set (core_sources
      diag.c
-- 
2.19.1