vasilito
cb424d7448
verify-patch-sanity.py validates every active recipe .patch has internally- consistent hunk line counts — catching the 'malformed patch at line N' failure at commit/CI/preflight time instead of hours into a cook. This cycle hit that class three times (qtwaylandscanner, sddm, xwayland), each only discovered when cookbook tried to apply the patch. Running it across the repo found 29 latent malformed patches (validated against GNU patch: e.g. relibc/P3-sysv-ipc reproduces 'malformed patch at line 22'). They were harmless only because they sit in vendored recipes (baked, not re- applied) — but would fail on any version-bump re-derivation. --fix recounts the hunk headers (body untouched) and repaired all 29. Wired into build-preflight.sh (Phase 1.0D) and redbear-ci.yml, with a unit test (test-patch-sanity.sh). Skips archived/legacy trees and unvalidatable formats (empty placeholders, bare-@@ git hunks).
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===================================================================
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How To Build On ARM
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===================================================================
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Introduction
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============
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This document contains information about building/testing LLVM and
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Clang on an ARM machine.
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This document is *NOT* tailored to help you cross-compile LLVM/Clang
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to ARM on another architecture, for example an x86_64 machine. To find
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out more about cross-compiling, please check :doc:`HowToCrossCompileLLVM`.
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Notes On Building LLVM/Clang on ARM
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=====================================
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Here are some notes on building/testing LLVM/Clang on ARM. Note that
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ARM encompasses a wide variety of CPUs; this advice is primarily based
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on the ARMv6 and ARMv7 architectures and may be inapplicable to older chips.
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#. The most popular Linaro/Ubuntu OS's for ARM boards, e.g., the
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Pandaboard, have become hard-float platforms. There are a number of
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choices when using CMake. Autoconf usage is deprecated as of 3.8.
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Building LLVM/Clang in ``Release`` mode is preferred since it consumes
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a lot less memory. Otherwise, the building process will very likely
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fail due to insufficient memory. It's also a lot quicker to only build
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the relevant back-ends (ARM and AArch64), since it's very unlikely that
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you'll use an ARM board to cross-compile to other arches. If you're
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running Compiler-RT tests, also include the x86 back-end, or some tests
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will fail.
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.. code-block:: bash
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cmake $LLVM_SRC_DIR -DCMAKE_BUILD_TYPE=Release \
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-DLLVM_TARGETS_TO_BUILD="ARM;X86;AArch64"
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Other options you can use are:
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.. code-block:: bash
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Use Ninja instead of Make: "-G Ninja"
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Build with assertions on: "-DLLVM_ENABLE_ASSERTIONS=True"
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Local (non-sudo) install path: "-DCMAKE_INSTALL_PREFIX=$HOME/llvm/install"
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CPU flags: "DCMAKE_C_FLAGS=-mcpu=cortex-a15" (same for CXX_FLAGS)
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After that, just typing ``make -jN`` or ``ninja`` will build everything.
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``make -jN check-all`` or ``ninja check-all`` will run all compiler tests. For
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running the test suite, please refer to :doc:`TestingGuide`.
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#. If you are building LLVM/Clang on an ARM board with 1G of memory or less,
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please use ``gold`` rather then GNU ``ld``. In any case it is probably a good
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idea to set up a swap partition, too.
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.. code-block:: bash
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$ sudo ln -sf /usr/bin/ld /usr/bin/ld.gold
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#. ARM development boards can be unstable and you may experience that cores
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are disappearing, caches being flushed on every big.LITTLE switch, and
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other similar issues. To help ease the effect of this, set the Linux
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scheduler to "performance" on **all** cores using this little script:
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.. code-block:: bash
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# The code below requires the package 'cpufrequtils' to be installed.
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for ((cpu=0; cpu<`grep -c proc /proc/cpuinfo`; cpu++)); do
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sudo cpufreq-set -c $cpu -g performance
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done
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Remember to turn that off after the build, or you may risk burning your
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CPU. Most modern kernels don't need that, so only use it if you have
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problems.
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#. Running the build on SD cards is ok, but they are more prone to failures
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than good quality USB sticks, and those are more prone to failures than
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external hard-drives (those are also a lot faster). So, at least, you
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should consider to buy a fast USB stick. On systems with a fast eMMC,
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that's a good option too.
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#. Make sure you have a decent power supply (dozens of dollars worth) that can
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provide *at least* 4 amperes, this is especially important if you use USB
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devices with your board. Externally powered USB/SATA harddrives are even
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better than having a good power supply.
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