Enable warnings-as-error for CI (#4659)

Enable warnings-as-error for CI

Closes #4664.

Uses glslang commit that fixed a compiler warning
Fixes a recent warning from external/CMakelist.txt
A new macro, `SLANG_MAYBE_UNUSED` is added for a future need.

8 files changed, 21 insertions, 9 deletions

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cdf315d8e..a45d7647c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -32,9 +32,11 @@ jobs:
           - { os: linux, runs-on: ubuntu-20.04 }
           - { os: macos, runs-on: macos-latest }
           - { os: windows, runs-on: windows-latest }
-          # When to have warnings
-          - warnings-as-errors: false
-          - { compiler: cl, warnings-as-errors true }
+          # Warnings are treated as errors by default.
+          # But we may want to disable it temporarily.
+          - { os: linux, warnings-as-errors: true }
+          - { os: macos, warnings-as-errors: true }
+          - { os: windows, warnings-as-errors: true }
           # Set a test category depending on the config, smoke by default,
           # quick or full conditionally otherwise
           - test-category: smoke
@@ -47,7 +49,6 @@ jobs:
             config: release
             compiler: gcc
             platform: aarch64
-            warnings-as-errors: false
             test-category: smoke
             full-gpu-tests: false
             runs-on: [self-hosted, Linux, ARM64]
@@ -56,7 +57,6 @@ jobs:
             config: release
             compiler: cl
             platform: x86_64
-            warnings-as-errors: false
             test-category: full
             full-gpu-tests: true
             runs-on: [Windows, self-hosted]
diff --git a/.github/workflows/compile-regression-test.yml b/.github/workflows/compile-regression-test.yml
index b6b484b9a..bd1011f86 100644
--- a/.github/workflows/compile-regression-test.yml
+++ b/.github/workflows/compile-regression-test.yml
@@ -21,7 +21,7 @@ jobs:
         platform: [x86_64]
         include:
           # Self-hosted falcor tests
-          - warnings-as-errors: false
+          - warnings-as-errors: true
             test-category: full
             full-gpu-tests: false
             runs-on: [Windows, self-hosted, regression-test]
diff --git a/.github/workflows/falcor-compiler-perf-test.yml b/.github/workflows/falcor-compiler-perf-test.yml
index 449944181..2fe168ade 100644
--- a/.github/workflows/falcor-compiler-perf-test.yml
+++ b/.github/workflows/falcor-compiler-perf-test.yml
@@ -23,7 +23,7 @@ jobs:
         platform: [x86_64]
         include:
           # Self-hosted falcor tests
-          - warnings-as-errors: false
+          - warnings-as-errors: true
             test-category: full
             full-gpu-tests: false
             runs-on: [Windows, self-hosted, perf]
diff --git a/.github/workflows/falcor-test.yml b/.github/workflows/falcor-test.yml
index 9dccb6af2..04c734bd4 100644
--- a/.github/workflows/falcor-test.yml
+++ b/.github/workflows/falcor-test.yml
@@ -21,7 +21,7 @@ jobs:
         platform: [x86_64]
         include:
           # Self-hosted falcor tests
-          - warnings-as-errors: false
+          - warnings-as-errors: true
             test-category: full
             full-gpu-tests: false
             runs-on: [Windows, self-hosted, falcor]
diff --git a/.github/workflows/vk-gl-cts-nightly.yml b/.github/workflows/vk-gl-cts-nightly.yml
index 374ea1b43..a835d20fc 100644
--- a/.github/workflows/vk-gl-cts-nightly.yml
+++ b/.github/workflows/vk-gl-cts-nightly.yml
@@ -18,7 +18,7 @@ jobs:
             compiler: cl
             platform: x86_64
             config: release
-            warnings-as-errors: false
+            warnings-as-errors: true
             test-category: full
             full-gpu-tests: false
             runs-on: [Windows, self-hosted]
diff --git a/external/CMakeLists.txt b/external/CMakeLists.txt
index 72a27285e..3ad07f10a 100644
--- a/external/CMakeLists.txt
+++ b/external/CMakeLists.txt
@@ -26,6 +26,12 @@ endif()
 # LZ4
 set(LZ4_BUNDLED_MODE ON)
 add_subdirectory(lz4/build/cmake EXCLUDE_FROM_ALL SYSTEM)
+if(MSVC)
+    target_compile_options(
+        lz4_static
+        PRIVATE /wd5045 /wd4820 /wd4711 /wd6385 /wd6262
+    )
+endif()
 
 # Vulkan headers
 add_subdirectory(vulkan EXCLUDE_FROM_ALL SYSTEM)
diff --git a/external/glslang b/external/glslang
-Subproject 4c20dc0cbb3b20d2afb9ee8595a39508f106662
+Subproject d86ef8a6e2b10508266ec8d63d64e866479d70d
diff --git a/include/slang.h b/include/slang.h
index 86ca4649b..76743a426 100644
--- a/include/slang.h
+++ b/include/slang.h
@@ -326,6 +326,12 @@ convention for interface methods.
 #	define SLANG_UNUSED(v) (void)v;
 #endif
 
+#if defined(__llvm__)
+#	define SLANG_MAYBE_UNUSED [[maybe_unused]]
+#else
+#	define SLANG_MAYBE_UNUSED
+#endif
+
 // Used for doing constant literals
 #ifndef SLANG_INT64
 #	define SLANG_INT64(x) (x##ll)