Permit to enable -Werror on builds, and enable by default for github actions.

.github/workflows/build-for-bookworm-wlroots-018.yml

@@ -81,7 +81,7 @@ jobs:
         export PKG_CONFIG_PATH="${{ env.INSTALL_PKGCONFIG_PATH }}"
         export LD_LIBRARY_PATH="${{ env.INSTALL_LIBRARY_PATH }}"
         export PATH="${PATH}:${{ env.INSTALL_PATH }}/bin"
-        cmake -DCMAKE_INSTALL_PREFIX:PATH=${{ env.INSTALL_PATH }} -B build/
+        cmake -DCMAKE_INSTALL_PREFIX:PATH=${{ env.INSTALL_PATH }} -Dconfig_WERROR=ON -B build/
 
     - name: Build wlmaker.
       run: |

.github/workflows/build-for-linux.yml

@@ -43,7 +43,7 @@ jobs:
     - name: Configure wlmaker through CMake.
       run: |
         export CC="${{ matrix.compiler }}"
-        cmake -B build/
+        cmake -B build/ -Dconfig_WERROR=ON
 
     - name: Build wlmaker.
       run: |

CMakeLists.txt

@@ -13,7 +13,7 @@
 # limitations under the License.
 #
 # Default arguments:
-# cmake -DCMAKE_INSTALL_PREFIX:PATH=${HOME}/.local -Dconfig_DOXYGEN_CRITICAL=ON -B build
+# cmake -DCMAKE_INSTALL_PREFIX:PATH=${HOME}/.local -Dconfig_DOXYGEN_CRITICAL=ON -Dconfig_WERROR=ON -B build
 # CC=clang cmake -DCMAKE_INSTALL_PREFIX:PATH=${HOME}/.local -Dconfig_DOXYGEN_CRITICAL=ON -B build-clang
 
 CMAKE_MINIMUM_REQUIRED(VERSION 3.13)
@@ -69,10 +69,14 @@ ENDIF(NOT WLROOTS_FOUND)
 OPTION(config_DEBUG "Include debugging information" ON)
 OPTION(config_OPTIM "Optimizations" OFF)
 OPTION(config_DOXYGEN_CRITICAL "Whether to fail on doxygen warnings" OFF)
+OPTION(config_WERROR "Make all compiler warnings into errors." OFF)
 
 # Toplevel compile options, for GCC and clang.
 IF(CMAKE_C_COMPILER_ID MATCHES "Clang|GNU")
   ADD_COMPILE_OPTIONS(-Wall -Wextra)
+  IF(config_WERROR)
+    ADD_COMPILE_OPTIONS(-Werror)
+  ENDIF(config_WERROR)
 
   IF(config_DEBUG)
     ADD_COMPILE_OPTIONS(-ggdb -DDEBUG)