diff --git a/.appveyor.yml b/.appveyor.yml
index 0c85fced..e594a151 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -65,6 +65,8 @@ before_build:
   - set "AV_CMAKE_ARGS=-DBUILD_SHARED_LIBS:BOOL=%shared%"
   - 'if %compiler%==mingw64-cmake set "PATH=C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64\bin;%PATH%"'
   - 'if %compiler%==mingw64-cmake set "AV_CMAKE_ARGS=%AV_CMAKE_ARGS% -DCMAKE_MAKE_PROGRAM=C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64\bin\mingw32-make"'
+  - 'if %compiler%==mingw64-cmake set CC=gcc'
+  - 'if %compiler%==mingw64-cmake set CXX=g++'
   - set "AV_TIFF_CMAKE_SOURCE=%AV_TIFF_SOURCE%"
   - set "AV_TIFF_CMAKE_INSTALL=%AV_TIFF_INSTALL%"
   - 'if %compiler%==cygwin-cmake set "AV_TIFF_CMAKE_SOURCE=%AV_TIFF_CYG_SOURCE%'