Remove warnings-as-errors by default

Compiling C++ on various different platforms with as many out of tree
dependencies as we have is volatile at best.
In order to prevent a third party warning from ruining the build for
people who don't care about third party warnings, we remove
warnings-as-errors by default.
They are still enabled by default on CI.

.appveyor.yml

@@ -13,6 +13,7 @@ environment:
     LLVM_LOC: '"C:\Program Files\LLVM\bin\"'
     PYTHON_LOC: '"C:\Python37\"'
     BUILD_PACKAGE: "1"
+    OVRAS_WARNINGS_AS_ERRORS: "1"
     
   - QT_LOC: '"C:\Qt\5.12\msvc2017_64\bin\"'
     VS_LOC: '"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build\vcvarsall.bat"'
@@ -23,6 +24,7 @@ environment:
     PYTHON_LOC: '"C:\Python37\"'
     BUILD_PACKAGE: "1"
     BUILD_CLANG: '"1"'
+    OVRAS_WARNINGS_AS_ERRORS: "1"
     
 
 clone_depth: 1
@@ -46,4 +48,4 @@ branches:
     - /docs-*/
     - /do-not-run-ci-*/
     - /only-travis-ci-*/
-    - /only-circle-ci-*/
+    - /only-circle-ci-*/

advancedSettings.pro

@@ -123,3 +123,7 @@ debugSymbolsAndLogs {
     CONFIG += force_debug_info
     DEFINES += ENABLE_DEBUG_LOGGING
 }
+
+warnings_as_errors {
+    message(Warnings as errors enabled.)
+}

build_scripts/linux/build_linux.sh

@@ -1,15 +1,30 @@
 #!/usr/bin/env bash
 set -e
+
+QMAKE_SPEC='linux-g++'
+
 SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 PROJECT_DIR=$SCRIPT_DIR/../../
 BUILD_DIR=$PROJECT_DIR/build/
-. $SCRIPT_DIR/configure.sh
+
+if [[ -z $USE_TIDY ]]; then
+    MAKE_COMMAND="make --jobs ${MAKE_JOBS}"
+    CLANG_TIDY=
+else
+    # Bear replaces the compile database, it does not update it.
+    # If you run 'bear make' and there is nothing to compile, you
+    # will get an empty database.
+    # Clean up the artifacts and run everything together in that case.
+    MAKE_COMMAND='bear make --jobs'
+    QMAKE_SPEC='linux-clang'
+    CLANG_TIDY="$SCRIPT_DIR/run-clang-tidy.sh"
+fi
 
 echo $MAKE_COMMAND
 mkdir -p $BUILD_DIR
 cd $BUILD_DIR
 qmake --version
-qmake -spec $QMAKE_SPEC $PROJECT_DIR $QMAKE_EXTRAS
+qmake -spec $QMAKE_SPEC $PROJECT_DIR CONFIG+=warnings_as_errors
 $MAKE_COMMAND
 $CLANG_TIDY
 

build_scripts/linux/configure.sh

@@ -1,26 +0,0 @@
-#!/usr/bin/env bash
-set -e
-
-if [[ -z $QMAKE_SPEC ]]; then
-    QMAKE_SPEC='linux-g++'
-fi
-
-if [[ -z $USE_TIDY ]]; then
-    MAKE_COMMAND="make --jobs ${MAKE_JOBS}"
-    CLANG_TIDY=
-else
-    # Bear replaces the compile database, it does not update it.
-    # If you run 'bear make' and there is nothing to compile, you
-    # will get an empty database.
-    # Clean up the artifacts and run everything together in that case.
-    MAKE_COMMAND='bear make --jobs'
-    QMAKE_SPEC='linux-clang'
-    CLANG_TIDY="$SCRIPT_DIR/run-clang-tidy.sh"
-fi
-
-if [[ -n $NO_X11 ]]; then
-    QMAKE_EXTRAS='CONFIG+=noX11'
-fi
-if [[ -n $NO_DBUS ]]; then
-    QMAKE_EXTRAS='CONFIG+=noDBUS'
-fi

build_scripts/qt/compilers/clang.pri

@@ -48,7 +48,10 @@ QMAKE_CXXFLAGS += -Wmost
 
 QMAKE_CXXFLAGS += -Wpedantic
 
-QMAKE_CXXFLAGS += -Werror
+warnings_as_errors {
+    QMAKE_CXXFLAGS += -Werror
+}
+
 #All includes from the third-party directory will not warn.
 QMAKE_CXXFLAGS += --system-header-prefix=third-party
 QMAKE_CXXFLAGS += --system-header-prefix=qt

build_scripts/qt/compilers/gcc.pri

@@ -27,7 +27,9 @@ include(clang-gcc-common-switches.pri)
 
 QMAKE_CXXFLAGS += -Wpedantic
 
-QMAKE_CXXFLAGS += -Werror
+warnings_as_errors {
+    QMAKE_CXXFLAGS += -Werror
+}
 
 # GCC only switches
 QMAKE_CXXFLAGS += -Wduplicated-branches -Wduplicated-cond -Wlogical-op -Wrestrict -Wnull-dereference

build_scripts/qt/compilers/msvc.pri

@@ -1,7 +1,9 @@
 include(common-msvc.pri)
 
-# Warnings as errors
+warnings_as_errors {
-QMAKE_CXXFLAGS += /WX
+    # Warnings as errors
+    QMAKE_CXXFLAGS += /WX
+}
 
 # Enables Link Time Optimization
 QMAKE_CXXFLAGS += /GL

build_scripts/win/build.py

@@ -139,7 +139,10 @@ def build():
         say(f"{BUILD_DEBUG_VAR_NAME} not defined. Building '{COMPILE_MODE}' version.")
 
     add_line_to_run_bat_file("@ECHO Running qmake:")
-    add_line_to_run_bat_file('"' + QMAKE_LOC + '"' +  " -spec " + COMPILER + " CONFIG+=X86_64 " + "CONFIG+=" + COMPILE_MODE)
+    if is_env_var_set("OVRAS_WARNINGS_AS_ERRORS"):
+    	add_line_to_run_bat_file('"' + QMAKE_LOC + '"' +  " -spec " + COMPILER + " CONFIG+=X86_64 " + "CONFIG+=" + COMPILE_MODE + " CONFIG+=warnings_as_errors")
+    else:
+    	add_line_to_run_bat_file('"' + QMAKE_LOC + '"' +  " -spec " + COMPILER + " CONFIG+=X86_64 " + "CONFIG+=" + COMPILE_MODE)
     add_error_handling_line_to_bat_file()
     add_line_to_run_bat_file("@ECHO qmake done.")
 

docs/building_for_linux.md

@@ -343,6 +343,7 @@ The following values can be appended to the `CONFIG` internal variable in order
 | `noDBUS` | Disables DBUS specific features (control media players). |
 | `noPulse` | Disables PulseAudio specific features (change audio devices). |
 | `debugSymbolsAndLogs` | Enables debug symbols and debug logging calls (while still having release optimizations). |
+| `warnings_as_errors` | Makes compiler warnings failing errors (not needed unless you're changing the source). |
 
 The values are case sensitive.
 
@@ -361,6 +362,11 @@ If you want to disable X11, DBUS and PulseAudio features you would type
 qmake CONFIG+=noX11 CONFIG+=noDBUS CONFIG+=noPulse
 ```
 
+If you want to compile with warnings as errors you would type
+```bash
+qmake CONFIG+=warnings_as_errors
+```
+
 The location for `make install` can be configured in the `qmake` step.
 This is done by setting the `PREFIX` variable.
 ```bash