Lower CMake requirement to 3.18.4

Author: danvratil

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.19)
+cmake_minimum_required(VERSION 3.18.4)
 set(qcoro_VERSION 0.6.0)
 set(qcoro_SOVERSION 0)
 project(qcoro LANGUAGES CXX VERSION ${qcoro_VERSION})

cmake/AddQCoroLibrary.cmake

@@ -105,12 +105,19 @@ function(add_qcoro_library)
     set_target_properties(
         ${target_name}
         PROPERTIES
-        WINDOWS_EXPORT_ALL_SYMBOLS 1
-        VERSION ${qcoro_VERSION}
-        SOVERSION ${qcoro_SOVERSION}
         EXPORT_NAME ${LIB_NAME}
     )
 
+    if (NOT LIB_INTERFACE)
+        set_target_properties(
+            ${target_name}
+            PROPERTIES
+            WINDOWS_EXPORT_ALL_SYMBOLS 1
+            VERSION ${qcoro_VERSION}
+            SOVERSION ${qcoro_SOVERSION}
+        )
+    endif()
+
     generate_headers(
         camelcase_HEADERS
         HEADER_NAMES ${LIB_CAMELCASE_HEADERS}