cmake: set empty CMAKE_DL_LIBS on MinGW

Upstream CMake sets CMAKE_DL_LIBS to an empty value on MINGW, but the
Fedora and RHEL packages override this and set "dl". Re-set it back to
an empty value.

We can revert this if https://bugzilla.redhat.com/2127529 is resolved
for CMake in Fedora and RHEL.

Signed-off-by: Ken Dreyer <kdreyer@redhat.com>

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 549b18bcfdf05e63ac03e8145d90e231d154c95f..8d6add4666b1e07101f2eca3531316faef72a20b 100644 (file)
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -249,6 +249,12 @@ if(COMPILER_SUPPORTS_DIAGNOSTICS_COLOR)
     "$<$<COMPILE_LANGUAGE:CXX>:-fdiagnostics-color=${DIAGNOSTICS_COLOR}>")
 endif()
 
+if(MINGW)
+  # Fedora and RHEL set CMAKE_DL_LIBS on MINGW, which we must un-set here.
+  # Details at https://bugzilla.redhat.com/show_bug.cgi?id=2127529
+  set(CMAKE_DL_LIBS "")
+endif()
+
 set(EXTRALIBS ${CMAKE_DL_LIBS})
 if(HAVE_POSIX_TIMERS)
   list(APPEND EXTRALIBS ${RT_LIBRARY})