Enable use of Ninja Multi-Config generator for Linux builds (#1017)

Author: MarkCallow

.github/workflows/linux.yml

@@ -58,25 +58,14 @@ jobs:
             doc: OFF, jni: ON, loadtests: OpenGL+Vulkan, py: ON, tools: ON, tools_cts: ON,
             sse: ON, opencl: OFF
           }
-        - name: Clang Debug
+        - name: Clang
           os: ubuntu-22.04
-          generator: Ninja
-          arch: x86_64
-          compiler: clang
-          vk_sdk_ver: '1.3.290'
-          options: {
-            config: Debug,
-            doc: OFF, jni: ON, loadtests: OpenGL+Vulkan, py: ON, tools: ON, tools_cts: OFF,
-            sse: ON, opencl: OFF
-          }
-        - name: Clang Release
-          os: ubuntu-22.04
-          generator: Ninja
+          generator: Ninja Multi-Config
           arch: x86_64
           compiler: clang
           vk_sdk_ver: '1.3.290'
           options: {
-            config: Release,
+            config: 'Debug,Release',
             doc: OFF, jni: ON, loadtests: OpenGL+Vulkan, py: ON, tools: ON, tools_cts: OFF,
             sse: ON, opencl: OFF
           }

scripts/build_linux.sh

@@ -54,25 +54,39 @@ if [[ "$ARCH" = "aarch64" && "$FEATURE_LOADTESTS" =~ "Vulkan" ]]; then
   else
     FEATURE_LOADTESTS=OpenGL
   fi
-  echo "Forcing FEATURE_LOADTESTS to \"$FEATURE_LOADTESTS\" as no Vulkan SDK yet for Linux/arm64."
+  echo "$0: Forcing FEATURE_LOADTESTS to \"$FEATURE_LOADTESTS\" as no Vulkan SDK yet for Linux/arm64."
 fi
 
+if [ ! "$CMAKE_GEN" = "Ninja Multi-Config" ]; then
+  # Single configuration generator.
+  if [[ "$CONFIGURATION" =~ "," ]]; then
+    echo "$0: Multiple build configurations specified with single-configuration CMake generator."
+    exit 1
+  fi
+fi
+
+cmake_args=("-G" "$CMAKE_GEN")
+
 if [[ -z $BUILD_DIR ]]; then
   BUILD_DIR=build/linux
   if [ "$ARCH" != $(uname -m) ]; then
     BUILD_DIR+="-$ARCH-"
   fi
-  if [ "$CMAKE_GEN" = "Ninja" -o "$CMAKE_GEN" = "Unix Makefiles" ]; then
-    # Single configuration generators.
+  if [ ! "$CMAKE_GEN" = "Ninja Multi-Config" ]; then
+    # Single configuration generator. That only a single configuration
+    # is specified has already been verified.
     BUILD_DIR+="-$CONFIGURATION"
+    CMAKE_BUILD_TYPE=$CONFIGURATION
   fi
 fi
+cmake_args+=("-B" $BUILD_DIR)
+if [ -n "$CMAKE_BUILD_TYPE" ]; then
+  cmake_args+=("-D" "CMAKE_BUILD_TYPE=$CMAKE_BUILD_TYPE")
+fi
 
 mkdir -p $BUILD_DIR
 
-cmake_args=("-G" "$CMAKE_GEN"
-  "-B" $BUILD_DIR \
-  "-D" "CMAKE_BUILD_TYPE=$CONFIGURATION" \
+cmake_args+=(\
   "-D" "KTX_FEATURE_DOC=$FEATURE_DOC" \
   "-D" "KTX_FEATURE_JNI=$FEATURE_JNI" \
   "-D" "KTX_FEATURE_LOADTEST_APPS=$FEATURE_LOADTESTS" \