SpiderMonkey is Mozilla's JavaScript and WebAssembly Engine, written in C++ and Rust. In BLFS, the source code of SpiderMonkey is taken from Firefox.
This package is known to build and work properly using an LFS 12.2 platform.
Download (HTTP): https://archive.mozilla.org/pub/firefox/releases/115.14.0esr/source/firefox-115.14.0esr.source.tar.xz
Download MD5 sum: deb750363b35d86629f824c0f8ba7f56
Download size: 484 MB
Estimated disk space required: 3.6 GB (40 MB installed after removing 36 MB static lib; add 34 MB for the main tests and 37 MB for the jit tests)
Estimated build time: 1.9 SBU (with parallelism=4; add 1.1 SBU for the main tests and 3.7 SBU for the jit tests)
ICU-75.1, rustc-1.80.1, and Which-2.21
LLVM-18.1.7 (with Clang, required for 32-bit systems without SSE2 capabilities)
![[Important]](../images/important.png) 
          
            If you are building this package on a 32-bit system, and Clang is
            not installed or you're overriding the default compiler choice
            with the environment variable CXX,
            please read the Command Explanations section first.
          
![[Note]](../images/note.png) 
          
            Unlike most other packages in BLFS, the instructions below
            require you to untar firefox-115.14.0esr.tar.xz and change into the
            firefox-115.14.0 directory.
          
            Extracting the tarball will reset the permissions of the current
            directory to 0755 if you have permission to do that. If you do
            this in a directory where the sticky bit is set, such as
            /tmp it will end with error
            messages:
          
              tar: .: Cannot utime: Operation not permitted
              tar: .: Cannot change mode to rwxr-xr-t: Operation not permitted
              tar: Exiting with failure status due to previous errors
            
            This does finish with non-zero status, but it does NOT mean there is a real problem. Do
            not untar as the root user in a
            directory where the sticky bit is set - that will unset it.
          
Install SpiderMonkey by running the following commands:
![[Note]](../images/note.png) 
          
            If you are compiling this package in chroot you must ensure that
            /dev/shm is mounted. If you do not
            do this, the Python
            configuration will fail with a traceback report referencing
            /usr/lib/pythonN.N/multiprocessing/synchronize.py.
            As the root user, run:
          
mountpoint -q /dev/shm || mount -t tmpfs devshm /dev/shm
Compiling the C++ code respects $MAKEFLAGS and defaults to 'j1', the rust code will use all processors.
mkdir obj &&
cd    obj &&
../js/src/configure --prefix=/usr            \
                    --disable-debug-symbols  \
                    --disable-jemalloc       \
                    --enable-readline        \
                    --with-intl-api          \
                    --with-system-icu        \
                    --with-system-zlib       &&
make
        To run the SpiderMonkey test suite, issue: make -C js/src check-jstests JSTESTS_EXTRA_ARGS="--timeout 300 --wpt=disabled". It's recommended to redirect the output into a log. Because we are building with system ICU, 39 tests (out of a total of more than 50,000) are known to fail. The test suite is executed with all CPU cores available: even in a cgroup with less cores assigned, it still attempts to spawn as many testing jobs as the number of all cores in the system; fortunately the kernel still won't run these jobs on cores not assigned to the cgroup so the CPU usage is still controlled.
          To run the JIT test suite, issue: make -C js/src check-jit-test
          JITTEST_EXTRA_ARGS="--timeout 300". Like the
          SpiderMonkey test suite, the number of test jobs is same as the
          number of all CPU cores in the system even if a cgroup is used. To
          make things worse, there are six tests which will use 3 GB each of
          system memory, so the peak memory usage may be up to 18 GB if the
          number of cores is six or more. Running the JIT test suite without
          enough memory may invoke the kernel OOM killer and cause stability
          issues. If you don't have enough system memory available, append
          -jN after --timeout 300 with N replaced by the number of
          parallel test jobs you want to start. For example, if you have 16
          GB system memory available and 8 CPU cores, issue make -C js/src check-jit-test
          JITTEST_EXTRA_ARGS="--timeout=300 -j5" to run the
          test with 5 parallel jobs so the memory usage won't exceed 15 GB.
        
![[Caution]](../images/caution.png) 
          An issue in the installation process causes any running program which links to SpiderMonkey shared library (for example, GNOME Shell) to crash if SpiderMonkey is reinstalled, or upgraded or downgraded without a change of the major version number (115 in 115.14.0). To work around this issue, remove the old version of the SpiderMonkey shared library before installation:
rm -fv /usr/lib/libmozjs-115.so
          Now, as the root user:
        
make install && rm -v /usr/lib/libjs_static.ajs && sed -i '/@NSPR_CFLAGS@/d' /usr/bin/js115-config
          --disable-debug-symbols:
          Don't generate debug symbols since they are very large and most
          users won't need it. Remove it if you want to debug SpiderMonkey.
        
          --disable-jemalloc: This
          switch disables the internal memory allocator used in SpiderMonkey.
          jemalloc is only intended for the Firefox browser environment. For
          other applications using SpiderMonkey, the application may crash as
          items allocated in the jemalloc allocator are freed on the system
          (glibc) allocator.
        
          --enable-readline: This
          switch enables Readline support in the SpiderMonkey command line
          interface.
        
          --with-intl-api: This
          enables the internationalization functions required by Gjs.
        
          --with-system-*: These
          parameters allow the build system to use system versions of the
          above libraries. These are required for stability.
        
rm -v /usr/lib/libjs_static.ajs: Remove a large static library which is not used by any BLFS package.
sed -i '/@NSPR_CFLAGS@/d' /usr/bin/js115-config: Prevent js115-config from using buggy CFLAGS.
          CC=gcc
          CXX=g++
          CXXFLAGS="-msse2
          -mfpmath=sse"