HPCC-26111 CMake smoketest build issue with CC/CXX 2

Signed-off-by: Mark Kelly <mark.kelly@lexisnexisrisk.com>

.github/workflows/smoketest.yml

@@ -272,6 +272,8 @@ jobs:
       if: ${{ steps.check-cache.outputs.state != '' }} # if 'state' set to anything, then step needed
       run: |
         cd build
+        echo "removing CMakeCache.txt"
+        rm -f CMakeCache.txt
         if [[ ! -f cache-timestamp ]]; then touch cache-timestamp; fi
         touch ../cmake-timestamp
         ../cmake/cmake ../src -Wno-dev -DRUNTIME_USER=$(whoami) -DRUNTIME_GROUP=$(id -gn) -DDESTDIR=$(realpath ..)/install -DINCLUDE_PLUGINS=1 -DCMAKE_BUILD_TYPE=RelWithDebInfo -DUSE_PYTHON2=0 -DUSE_PYTHON3=1 -DSUPPRESS_SPARK=1 -DUSE_CPPUNIT=1 -DUSE_CASSANDRA=Off -DCMAKE_CXX_FLAGS="-DBUILD_TAG=\\\"dummytag\\\" -DBUILD_VERSION_MAJOR=1 -DBUILD_VERSION_MINOR=1 -DBUILD_VERSION_POINT=0" -DBUILD_TAG="smoketest"

CMakeLists.txt

@@ -67,7 +67,7 @@
 #
 #########################################################
 
-project(hpccsystems-platform)
+project(hpccsystems-platform LANGUAGES C CXX)
 
 # Stupid workaround. See https://gitlab.kitware.com/cmake/cmake/-/issues/21378
 # If cmake runs twice, cmake might not correctly set the compiler version variables