build: wasm: wamrc: Make WAMR and its toolchain buildable on raspbian

[cosmo0920]

Signed-off-by: Hiroshi Hatake [email protected]

In raspbian, its provided gcc does not support -mindirect-branch-register compiler option. We should check whether the compiler option is supported or not before specifying it on C_FLAGS.

Also, we have to handle armv6 or armv7 platform on our CMakeLists.txt for WAMR,

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• [ ] Example configuration file for the change
• [ ] Debug log output from testing the change

• [ ] Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• [x] Attached local packaging test output showing all targets (including any new ones) build.

# ...
checking size of int... no
checking for TLS... [ 15%] Building C object src/wasm/CMakeFiles/vmlib-static.dir/__/__/lib/wasm-micro-runtime-fast-jit-06-29-2022/core/iwasm/libraries/thread-mgr/thread_manager.c.o
yes
checking whether C11 atomics is compilable... [ 16%] Linking C static library ../../../library/libxxhash.a
4
checking size of short... no
checking whether GCC __atomic atomics is compilable... [ 16%] Built target xxhash
Scanning dependencies of target snappy-c
[ 16%] Building C object lib/snappy-fef67ac/CMakeFiles/snappy-c.dir/snappy.c.o
[ 16%] Linking C static library ../../library/libvmlib-static.a
[ 16%] Built target vmlib-static

The details of building log is attached: raspbian-build.log

Documentation

• [ ] Documentation required for this feature

Backporting

• [ ] Backport to latest stable release.

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Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.

[cosmo0920]

We need to this PR to build WAMR for armv7 or armv6 environment such as raspbian.