Everywhere: Require version >= 12 for GCC host compiler

So far we've gotten away with using GCC 11 for Lagom and to compile the
toolchain, but via #15795 we discovered a compiler bug that has been
fixed in the latest version but would error the build with CI's GCC 11.
Time for an upgrade :^)

We already use ubuntu-22.04 images in most places, so this is pretty
straightforward. The only exception is Idan's self-hosted runner, which
uses Ubuntu Focal. LibJS should build fine with GCC 11, still.

11 files changed, 40 insertions, 44 deletions

diff --git a/.github/workflows/cmake.yml b/.github/workflows/cmake.yml
index 8b8e0af859..74e411e803 100644
--- a/.github/workflows/cmake.yml
+++ b/.github/workflows/cmake.yml
@@ -47,7 +47,7 @@ jobs:
           wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
           sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-14 main'
           sudo apt-get update
-          sudo apt-get install -y clang-format-14 ccache e2fsprogs gcc-11 g++-11 libstdc++-11-dev libmpfr-dev libmpc-dev ninja-build optipng qemu-utils qemu-system-i386 unzip
+          sudo apt-get install -y clang-format-14 ccache e2fsprogs gcc-12 g++-12 libstdc++-12-dev libmpfr-dev libmpc-dev ninja-build optipng qemu-utils qemu-system-i386 unzip
       - name: Install JS dependencies
         run: sudo npm install -g prettier@2.7.1
       - name: Install Python dependencies
@@ -56,7 +56,7 @@ jobs:
           python -m pip install --upgrade pip
           pip install flake8 requests
       - name: Check versions
-        run: set +e; g++ --version; g++-11 --version; clang-format --version; clang-format-14 --version; prettier --version; python --version; python3 --version; ninja --version; flake8 --version; ccache --version; qemu-system-i386 --version
+        run: set +e; g++ --version; g++-12 --version; clang-format --version; clang-format-14 --version; prettier --version; python --version; python3 --version; ninja --version; flake8 --version; ccache --version; qemu-system-i386 --version
 
       # === PREPARE FOR BUILDING ===
 
@@ -147,8 +147,8 @@ jobs:
             -DSERENITY_ARCH=${{ matrix.arch }} \
             -DSERENITY_TOOLCHAIN=GNU \
             -DBUILD_LAGOM=ON \
-            -DCMAKE_C_COMPILER=gcc-11 \
-            -DCMAKE_CXX_COMPILER=g++-11 \
+            -DCMAKE_C_COMPILER=gcc-12 \
+            -DCMAKE_CXX_COMPILER=g++-12 \
             -DENABLE_ALL_DEBUG_FACILITIES=ON \
             -DENABLE_PCI_IDS_DOWNLOAD=OFF \
             -DENABLE_USB_IDS_DOWNLOAD=OFF
@@ -161,8 +161,8 @@ jobs:
           cmake -S Meta/CMake/Superbuild -B Build/superbuild -GNinja \
             -DSERENITY_ARCH=${{ matrix.arch }} \
             -DSERENITY_TOOLCHAIN=GNU \
-            -DCMAKE_C_COMPILER=gcc-11 \
-            -DCMAKE_CXX_COMPILER=g++-11 \
+            -DCMAKE_C_COMPILER=gcc-12 \
+            -DCMAKE_CXX_COMPILER=g++-12 \
             -DENABLE_UNDEFINED_SANITIZER=ON \
             -DDUMP_REGIONS_ON_CRASH=ON \
             -DENABLE_PCI_IDS_DOWNLOAD=OFF \
diff --git a/.github/workflows/pvs-studio-static-analysis.yml b/.github/workflows/pvs-studio-static-analysis.yml
index 6eef54734b..59793b0b6a 100644
--- a/.github/workflows/pvs-studio-static-analysis.yml
+++ b/.github/workflows/pvs-studio-static-analysis.yml
@@ -28,10 +28,10 @@ jobs:
           wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
           sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-14 main'
           sudo apt-get update
-          sudo apt-get install -y clang-format-14 gcc-11 g++-11 libstdc++-11-dev libmpfr-dev libmpc-dev ninja-build unzip pvs-studio
+          sudo apt-get install -y clang-format-14 gcc-12 g++-12 libstdc++-12-dev libmpfr-dev libmpc-dev ninja-build unzip pvs-studio
 
       - name: Check versions
-        run: set +e; g++ --version; g++-11 --version; ninja --version;
+        run: set +e; g++ --version; g++-12 --version; ninja --version;
 
       - name: Prepare useful stamps
         id: stamps
@@ -73,8 +73,8 @@ jobs:
           cmake -S Meta/CMake/Superbuild -B Build/superbuild -GNinja \
             -DSERENITY_ARCH=${{ env.PVS_STUDIO_ANALYSIS_ARCH }} \
             -DSERENITY_TOOLCHAIN=GNU \
-            -DCMAKE_C_COMPILER=gcc-11 \
-            -DCMAKE_CXX_COMPILER=g++-11 \
+            -DCMAKE_C_COMPILER=gcc-12 \
+            -DCMAKE_CXX_COMPILER=g++-12 \
             -DENABLE_PCI_IDS_DOWNLOAD=OFF \
             -DENABLE_USB_IDS_DOWNLOAD=OFF
 
diff --git a/.github/workflows/sonar-cloud-static-analysis.yml b/.github/workflows/sonar-cloud-static-analysis.yml
index 647b57bb33..61c033e0ff 100644
--- a/.github/workflows/sonar-cloud-static-analysis.yml
+++ b/.github/workflows/sonar-cloud-static-analysis.yml
@@ -61,10 +61,10 @@ jobs:
           wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
           sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-14 main'
           sudo apt-get update
-          sudo apt-get install -y clang-format-14 gcc-11 g++-11 libstdc++-11-dev libmpfr-dev libmpc-dev ninja-build unzip
+          sudo apt-get install -y clang-format-14 gcc-12 g++-12 libstdc++-12-dev libmpfr-dev libmpc-dev ninja-build unzip
 
       - name: Check versions
-        run: set +e; g++ --version; g++-11 --version; ninja --version;
+        run: set +e; g++ --version; g++-12 --version; ninja --version;
 
       - name: Prepare useful stamps
         id: stamps
@@ -106,8 +106,8 @@ jobs:
           cmake -S Meta/CMake/Superbuild -B Build/superbuild -GNinja \
             -DSERENITY_ARCH=${{ env.SONAR_ANALYSIS_ARCH }} \
             -DSERENITY_TOOLCHAIN=GNU \
-            -DCMAKE_C_COMPILER=gcc-11 \
-            -DCMAKE_CXX_COMPILER=g++-11 \
+            -DCMAKE_C_COMPILER=gcc-12 \
+            -DCMAKE_CXX_COMPILER=g++-12 \
             -DENABLE_PCI_IDS_DOWNLOAD=OFF \
             -DENABLE_USB_IDS_DOWNLOAD=OFF
 
diff --git a/Documentation/BuildInstructions.md b/Documentation/BuildInstructions.md
index 9885b0d404..8fd2bed074 100644
--- a/Documentation/BuildInstructions.md
+++ b/Documentation/BuildInstructions.md
@@ -11,13 +11,10 @@ sudo apt install build-essential cmake curl libmpfr-dev libmpc-dev libgmp-dev e2
 ```
 Optional: `fuse2fs` for [building images without root](https://github.com/SerenityOS/serenity/pull/11224).
 
-#### GCC 11
+#### GCC 12
 
-On Ubuntu gcc-11 is available in the repositories of 21.04 (Hirsuite) and later - add the `ubuntu-toolchain-r/test` PPA if you're running an older version:
-
-```console
-sudo add-apt-repository ppa:ubuntu-toolchain-r/test
-```
+On Ubuntu gcc-12 is available in the repositories of 22.04 (Jammy) and later.
+If you are running an older version, you will either need to upgrade, or find an alternative installation source.
 
 Next, update your local package information from this repository:
 
@@ -25,10 +22,10 @@ Next, update your local package information from this repository:
 sudo apt update
 ```
 
-Now on Ubuntu or Debian you can install gcc-11 with apt like this:
+Now on Ubuntu or Debian you can install gcc-12 with apt like this:
 
 ```console
-sudo apt install gcc-11 g++-11
+sudo apt install gcc-12 g++-12
 ```
 
 #### QEMU 6.2 or later
diff --git a/Documentation/SelfHostedRunners.md b/Documentation/SelfHostedRunners.md
index 5cfccba16f..fb99c251c4 100644
--- a/Documentation/SelfHostedRunners.md
+++ b/Documentation/SelfHostedRunners.md
@@ -14,20 +14,19 @@ As for recommended requirements, listed below are the specifications of the curr
 
 ## Setup
 
-These instructions assume the OS installed is Ubuntu 20.04 (Focal), so they might not be compatible with other Linux flavours.
+These instructions assume the OS installed is Ubuntu 22.04 (Jammy), so they might not be compatible with other Linux flavours.
 
 ### Install base dependencies
 ```shell
 sudo add-apt-repository ppa:canonical-server/server-backports
-sudo add-apt-repository ppa:ubuntu-toolchain-r/test
 wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
-sudo add-apt-repository 'deb http://apt.llvm.org/focal/ llvm-toolchain-focal-14 main'
+sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-focal-14 main'
 apt update
-apt install git build-essential make cmake clang-format-14 gcc-11 g++-11 libstdc++-11-dev libgmp-dev ccache libmpfr-dev libmpc-dev ninja-build e2fsprogs qemu-utils qemu-system-i386 wabt
+apt install git build-essential make cmake clang-format-14 gcc-12 g++-12 libstdc++-12-dev libgmp-dev ccache libmpfr-dev libmpc-dev ninja-build e2fsprogs qemu-utils qemu-system-i386 wabt
 ```
-### Force usage of GCC 11
+### Force usage of GCC 12
 ```shell
-update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-12 100 --slave /usr/bin/g++ g++ /usr/bin/g++-12
 ```
 ### Create a new user account named 'runner'
 ```shell
diff --git a/Documentation/Troubleshooting.md b/Documentation/Troubleshooting.md
index 4b41a94954..b5a3752b62 100644
--- a/Documentation/Troubleshooting.md
+++ b/Documentation/Troubleshooting.md
@@ -16,9 +16,9 @@ install it. You can also build it using the `Toolchain/BuildQemu.sh` script.
 
 ### GCC is missing or is outdated
 
-Ensure your gcc version is >= 11 with `gcc --version`. Otherwise, install it. If your gcc binary is not
+Ensure your gcc version is >= 12 with `gcc --version`. Otherwise, install it. If your gcc binary is not
 called `gcc` you have to specify the names of your C and C++ compiler when you run cmake, e.g.
-`cmake ../.. -GNinja -DCMAKE_C_COMPILER=gcc-11 -DCMAKE_CXX_COMPILER=g++-11`.
+`cmake ../.. -GNinja -DCMAKE_C_COMPILER=gcc-12 -DCMAKE_CXX_COMPILER=g++-12`.
 
 ## Running SerenityOS
 
diff --git a/Meta/Azure/Lagom.yml b/Meta/Azure/Lagom.yml
index 253b146d4c..41c394fa1b 100644
--- a/Meta/Azure/Lagom.yml
+++ b/Meta/Azure/Lagom.yml
@@ -102,8 +102,8 @@ jobs:
             -DWASM_SPEC_TEST_SKIP_FORMATTING=ON \
             -DENABLE_UNDEFINED_SANITIZER=ON \
             -DENABLE_ADDRESS_SANITIZER=ON \
-            -DCMAKE_C_COMPILER=gcc-11 \
-            -DCMAKE_CXX_COMPILER=g++-11
+            -DCMAKE_C_COMPILER=gcc-12 \
+            -DCMAKE_CXX_COMPILER=g++-12
         displayName: 'Create Build Environment'
         workingDirectory: $(Build.SourcesDirectory)/Meta/Lagom
         env:
diff --git a/Meta/Azure/Serenity.yml b/Meta/Azure/Serenity.yml
index 65aa7d927b..0d75f001f0 100644
--- a/Meta/Azure/Serenity.yml
+++ b/Meta/Azure/Serenity.yml
@@ -50,8 +50,8 @@ jobs:
           -DDUMP_REGIONS_ON_CRASH=ON \
           -DENABLE_PCI_IDS_DOWNLOAD=OFF \
           -DENABLE_USB_IDS_DOWNLOAD=OFF \
-          -DCMAKE_C_COMPILER=gcc-11 \
-          -DCMAKE_CXX_COMPILER=g++-11
+          -DCMAKE_C_COMPILER=gcc-12 \
+          -DCMAKE_CXX_COMPILER=g++-12
       displayName: 'Create Build Environment'
       workingDirectory: $(Build.SourcesDirectory)
       env:
diff --git a/Meta/Azure/Setup.yml b/Meta/Azure/Setup.yml
index 53d12d4354..21aaf77d24 100644
--- a/Meta/Azure/Setup.yml
+++ b/Meta/Azure/Setup.yml
@@ -10,21 +10,21 @@ steps:
         wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
         sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-14 main'
         sudo apt-get update
-        sudo apt-get install clang-format-14 ccache e2fsprogs gcc-11 g++-11 libstdc++-11-dev libmpfr-dev libmpc-dev ninja-build qemu-utils qemu-system-i386 unzip lld
+        sudo apt-get install clang-format-14 ccache e2fsprogs gcc-12 g++-12 libstdc++-12-dev libmpfr-dev libmpc-dev ninja-build qemu-utils qemu-system-i386 unzip lld
       displayName: 'Install Dependencies'
 
   - ${{ if eq(parameters.os, 'Linux') }}:
     - script: |
-        sudo apt-get purge -y clang-11 clang-12 gcc-10
+        sudo apt-get purge -y clang-12 gcc-10
         wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
         sudo add-apt-repository 'deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-13 main'
         sudo apt-get update
-        sudo apt-get install ccache gcc-11 g++-11 clang-13 libstdc++-11-dev ninja-build unzip
+        sudo apt-get install ccache gcc-12 g++-12 clang-13 libstdc++-12-dev ninja-build unzip
 
         sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-13 100
         sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-13 100
-        sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 100
-        sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-11 100
+        sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-12 100
+        sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-12 100
 
         wget https://github.com/WebAssembly/wabt/releases/download/1.0.23/wabt-1.0.23-ubuntu.tar.gz
         tar -xzf ./wabt-1.0.23-ubuntu.tar.gz
diff --git a/Meta/serenity.sh b/Meta/serenity.sh
index ed171e55b2..63ce4cbfcd 100755
--- a/Meta/serenity.sh
+++ b/Meta/serenity.sh
@@ -192,7 +192,7 @@ pick_host_compiler() {
         return
     fi
 
-    find_newest_compiler egcc gcc gcc-11 gcc-12 /usr/local/bin/gcc-11 /opt/homebrew/bin/gcc-11
+    find_newest_compiler egcc gcc gcc-12 /usr/local/bin/gcc-12 /opt/homebrew/bin/gcc-12
     if is_supported_compiler "$HOST_COMPILER"; then
         export CC="${HOST_COMPILER}"
         export CXX="${HOST_COMPILER/gcc/g++}"
@@ -206,7 +206,7 @@ pick_host_compiler() {
         return
     fi
 
-    die "Please make sure that GCC version 11, Clang version 13, or higher is installed."
+    die "Please make sure that GCC version 12, Clang version 13, or higher is installed."
 }
 
 cmd_with_target() {
diff --git a/Toolchain/Dockerfile b/Toolchain/Dockerfile
index cb64d63ff3..a8af4f36d6 100644
--- a/Toolchain/Dockerfile
+++ b/Toolchain/Dockerfile
@@ -8,8 +8,8 @@ RUN apt-get update -y \
         ccache \
         cmake \
         curl \
-        g++-11 \
-        gcc-11 \
+        g++-12 \
+        gcc-12 \
         e2fsprogs \
         genext2fs \
         git \
@@ -29,4 +29,4 @@ RUN apt-get update -y \
         tzdata \
         unzip \
     && rm -rf /var/lib/apt/lists/ \
-    && update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 900 --slave /usr/bin/g++ g++ /usr/bin/g++-11
+    && update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-12 900 --slave /usr/bin/g++ g++ /usr/bin/g++-12