From 1d0da6c21b7536d0bff7839bfd2497dedfdfe15e Mon Sep 17 00:00:00 2001
From: River <26424577+wusatosi@users.noreply.github.com>
Date: Tue, 30 Sep 2025 20:40:45 +0000
Subject: [PATCH 1/4] add initial Dockerfile for building llvm

---
 Dockerfile.clang.ubuntu | 52 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)
 create mode 100644 Dockerfile.clang.ubuntu

diff --git a/Dockerfile.clang.ubuntu b/Dockerfile.clang.ubuntu
new file mode 100644
index 0000000..8870c3c
--- /dev/null
+++ b/Dockerfile.clang.ubuntu
@@ -0,0 +1,52 @@
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+FROM ubuntu:24.04
+
+ARG LLVM_VERSION=19.1.7
+ARG NUM_JOBS=4
+
+# Install build dependencies
+RUN apt-get update && \
+    DEBIAN_FRONTEND=noninteractive apt-get install -y \
+    build-essential \
+    cmake \
+    ninja-build \
+    git \
+    python3 \
+    python3-pip \
+    wget \
+    ca-certificates \
+    && rm -rf /var/lib/apt/lists/*
+
+# Download and extract LLVM source
+WORKDIR /tmp
+RUN wget https://github.com/llvm/llvm-project/releases/download/llvmorg-${LLVM_VERSION}/llvm-project-${LLVM_VERSION}.src.tar.xz && \
+    tar -xf llvm-project-${LLVM_VERSION}.src.tar.xz && \
+    rm llvm-project-${LLVM_VERSION}.src.tar.xz
+
+# Build LLVM/Clang (optimized for build speed)
+WORKDIR /tmp/llvm-project-${LLVM_VERSION}.src
+RUN cmake -S llvm -B build -G Ninja \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DCMAKE_INSTALL_PREFIX=/usr/local \
+    -DLLVM_ENABLE_PROJECTS="clang" \
+    -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi" \
+    -DLLVM_TARGETS_TO_BUILD="X86" \
+    -DLLVM_INCLUDE_BENCHMARKS=OFF \
+    -DLLVM_INCLUDE_TESTS=OFF \
+    -DLLVM_INCLUDE_EXAMPLES=OFF \
+    -DLLVM_INCLUDE_DOCS=OFF \
+    -DLLVM_ENABLE_ASSERTIONS=OFF \
+    -DLLVM_ENABLE_BACKTRACES=OFF \
+    -DLLVM_OPTIMIZED_TABLEGEN=ON \
+    -DCLANG_ENABLE_ARCMT=OFF \
+    -DCLANG_ENABLE_STATIC_ANALYZER=OFF \
+    && ninja -C build -j${NUM_JOBS} \
+    && ninja -C build install \
+    && rm -rf /tmp/llvm-project-${LLVM_VERSION}.src
+
+# Verify installation
+RUN clang --version && clang++ --version
+
+WORKDIR /workspace
+CMD ["/bin/bash"]

From b1b5df2499dca5f8786465b86b45e79946611bf7 Mon Sep 17 00:00:00 2001
From: wusatosi <26424577+wusatosi@users.noreply.github.com>
Date: Tue, 30 Sep 2025 23:56:48 +0000
Subject: [PATCH 2/4] clang building

---
 Dockerfile.clang.ubuntu | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/Dockerfile.clang.ubuntu b/Dockerfile.clang.ubuntu
index 8870c3c..c5cc826 100644
--- a/Dockerfile.clang.ubuntu
+++ b/Dockerfile.clang.ubuntu
@@ -3,7 +3,6 @@
 FROM ubuntu:24.04
 
 ARG LLVM_VERSION=19.1.7
-ARG NUM_JOBS=4
 
 # Install build dependencies
 RUN apt-get update && \
@@ -25,12 +24,12 @@ RUN wget https://github.com/llvm/llvm-project/releases/download/llvmorg-${LLVM_V
     rm llvm-project-${LLVM_VERSION}.src.tar.xz
 
 # Build LLVM/Clang (optimized for build speed)
+ARG NUM_JOBS=4
 WORKDIR /tmp/llvm-project-${LLVM_VERSION}.src
 RUN cmake -S llvm -B build -G Ninja \
     -DCMAKE_BUILD_TYPE=Release \
     -DCMAKE_INSTALL_PREFIX=/usr/local \
     -DLLVM_ENABLE_PROJECTS="clang" \
-    -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi" \
     -DLLVM_TARGETS_TO_BUILD="X86" \
     -DLLVM_INCLUDE_BENCHMARKS=OFF \
     -DLLVM_INCLUDE_TESTS=OFF \

From 6f6ecc37843d0b569bca6bd84c618d44dc286b97 Mon Sep 17 00:00:00 2001
From: wusatosi <26424577+wusatosi@users.noreply.github.com>
Date: Wed, 1 Oct 2025 05:44:08 +0000
Subject: [PATCH 3/4] add docs & separate build steps

---
 Dockerfile.clang.ubuntu | 34 +++++++++++++++++++++++++++++++---
 1 file changed, 31 insertions(+), 3 deletions(-)

diff --git a/Dockerfile.clang.ubuntu b/Dockerfile.clang.ubuntu
index c5cc826..66f0d9d 100644
--- a/Dockerfile.clang.ubuntu
+++ b/Dockerfile.clang.ubuntu
@@ -1,5 +1,31 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+# Dockerfile for building LLVM/Clang from source on Ubuntu 24.04
+#
+# This Dockerfile builds a custom Clang compiler tagged with a specific release.
+#
+# The build is setup to minimize build time, thus it disables unnecessary components
+# (tests, examples, docs, static analyzer, etc.) and only targets X86 architecture.
+#
+# Build arguments:
+#   LLVM_VERSION - LLVM version to build
+#   NUM_JOBS     - Number of parallel build jobs (default: 4)
+#
+# Usage:
+#   Build with default settings:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:19 .
+#
+#   Build with custom parallelism:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:19 --build-arg NUM_JOBS=6 .
+#
+#   Build different LLVM version:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:20 --build-arg LLVM_VERSION=20.0.0 .
+#
+# The built image includes:
+#   - clang and clang++ compilers at /usr/local
+#
+# TODO: figure out how to get the tarball from nightly/ specific branch
+
 FROM ubuntu:24.04
 
 ARG LLVM_VERSION=19.1.7
@@ -39,9 +65,11 @@ RUN cmake -S llvm -B build -G Ninja \
     -DLLVM_ENABLE_BACKTRACES=OFF \
     -DLLVM_OPTIMIZED_TABLEGEN=ON \
     -DCLANG_ENABLE_ARCMT=OFF \
-    -DCLANG_ENABLE_STATIC_ANALYZER=OFF \
-    && ninja -C build -j${NUM_JOBS} \
-    && ninja -C build install \
+    -DCLANG_ENABLE_STATIC_ANALYZER=OFF
+
+RUN ninja -C build -j${NUM_JOBS}
+
+RUN ninja -C build install \
     && rm -rf /tmp/llvm-project-${LLVM_VERSION}.src
 
 # Verify installation

From 295a85c4a3bf8dea868b0dca9b6d4db51df3780e Mon Sep 17 00:00:00 2001
From: wusatosi <26424577+wusatosi@users.noreply.github.com>
Date: Mon, 6 Oct 2025 03:23:32 +0000
Subject: [PATCH 4/4] allow build from arbitary link

---
 Dockerfile.clang.ubuntu | 51 ++++++++++++++++++++++++++---------------
 1 file changed, 33 insertions(+), 18 deletions(-)

diff --git a/Dockerfile.clang.ubuntu b/Dockerfile.clang.ubuntu
index 66f0d9d..4e251e5 100644
--- a/Dockerfile.clang.ubuntu
+++ b/Dockerfile.clang.ubuntu
@@ -8,28 +8,41 @@
 # (tests, examples, docs, static analyzer, etc.) and only targets X86 architecture.
 #
 # Build arguments:
-#   LLVM_VERSION - LLVM version to build
+#   LLVM_GIT_URL - Git repository URL (default: https://github.com/llvm/llvm-project.git)
+#   LLVM_GIT_REF - Git branch/tag/commit to build from (default: llvmorg-21.1.2)
 #   NUM_JOBS     - Number of parallel build jobs (default: 4)
 #
 # Usage:
-#   Build with default settings:
-#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:19 .
+#   Build from default release tag (llvm 21.1.2)
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:21 .
 #
-#   Build with custom parallelism:
-#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:19 --build-arg NUM_JOBS=6 .
+#   Build from different release tag:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:19 --build-arg LLVM_GIT_REF=llvmorg-19.1.7 .
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:20 --build-arg LLVM_GIT_REF=llvmorg-20.1.8 .
+#
+#   Build from release branch (tracks latest stable):
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:20 --build-arg LLVM_GIT_REF=release/20.x .
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:21 --build-arg LLVM_GIT_REF=release/21.x .
+#
+#   Build from main branch (nightly):
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:main --build-arg LLVM_GIT_REF=main .
 #
-#   Build different LLVM version:
-#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:20 --build-arg LLVM_VERSION=20.0.0 .
+#   Build from specific commit:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:custom --build-arg LLVM_GIT_REF=abc123def .
+#
+#   Build from fork or mirror:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:custom \
+#       --build-arg LLVM_GIT_URL=https://github.com/yourfork/llvm-project.git \
+#       --build-arg LLVM_GIT_REF=your-branch .
+#
+#   Build with custom parallelism:
+#     docker build -f Dockerfile.clang.ubuntu -t clang-ubuntu:21 --build-arg NUM_JOBS=8 .
 #
 # The built image includes:
 #   - clang and clang++ compilers at /usr/local
-#
-# TODO: figure out how to get the tarball from nightly/ specific branch
 
 FROM ubuntu:24.04
 
-ARG LLVM_VERSION=19.1.7
-
 # Install build dependencies
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y \
@@ -43,20 +56,22 @@ RUN apt-get update && \
     ca-certificates \
     && rm -rf /var/lib/apt/lists/*
 
-# Download and extract LLVM source
+# Clone LLVM source from git
+ARG LLVM_GIT_URL=https://github.com/llvm/llvm-project.git
+ARG LLVM_GIT_REF=llvmorg-21.1.2
+
 WORKDIR /tmp
-RUN wget https://github.com/llvm/llvm-project/releases/download/llvmorg-${LLVM_VERSION}/llvm-project-${LLVM_VERSION}.src.tar.xz && \
-    tar -xf llvm-project-${LLVM_VERSION}.src.tar.xz && \
-    rm llvm-project-${LLVM_VERSION}.src.tar.xz
+RUN echo "Building from $LLVM_GIT_URL @ $LLVM_GIT_REF" && \
+    git clone --depth 1 --branch "$LLVM_GIT_REF" "$LLVM_GIT_URL" llvm-project-src
 
 # Build LLVM/Clang (optimized for build speed)
 ARG NUM_JOBS=4
-WORKDIR /tmp/llvm-project-${LLVM_VERSION}.src
+WORKDIR /tmp/llvm-project-src
 RUN cmake -S llvm -B build -G Ninja \
     -DCMAKE_BUILD_TYPE=Release \
     -DCMAKE_INSTALL_PREFIX=/usr/local \
     -DLLVM_ENABLE_PROJECTS="clang" \
-    -DLLVM_TARGETS_TO_BUILD="X86" \
+    -DLLVM_TARGETS_TO_BUILD="X86;AArch64" \
     -DLLVM_INCLUDE_BENCHMARKS=OFF \
     -DLLVM_INCLUDE_TESTS=OFF \
     -DLLVM_INCLUDE_EXAMPLES=OFF \
@@ -70,7 +85,7 @@ RUN cmake -S llvm -B build -G Ninja \
 RUN ninja -C build -j${NUM_JOBS}
 
 RUN ninja -C build install \
-    && rm -rf /tmp/llvm-project-${LLVM_VERSION}.src
+    && rm -rf /tmp/llvm-project-src
 
 # Verify installation
 RUN clang --version && clang++ --version