42735cb9b9
Until now, we were assuming that whenever you have gcc 4.8, libatomic is available. It turns out that this is not correct, since libatomic will not be available if thread support is disabled in the toolchain. Therefore, __atomic_*() intrinsics may not be available even if the toolchain uses gcc 4.8. To solve this problem, we introduce a BR2_TOOLCHAIN_HAS_LIBATOMIC boolean, which indicates whether the toolchain has libatomic. It is the case when you are using gcc >= 4.8 *and* thread support is enabled. We then use this new BR2_TOOLCHAIN_HAS_LIBATOMIC to define BR2_TOOLCHAIN_HAS_ATOMIC. As explained in the comment, on certain architectures, libatomic is technically not needed to provide the __atomic_*() intrinsics since they might be all built-in. However, since libatomic is only absent in non-thread capable toolchains, it is not worth making things more complex for such seldomly used configuration. Note that we are introducing the intermediate BR2_TOOLCHAIN_HAS_LIBATOMIC option because it will be useful on its own for certain packages. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> [Thomas: improve Config.in comment using a suggestion from Yann.] |
||
|---|---|---|
| arch | ||
| board | ||
| boot | ||
| configs | ||
| docs | ||
| fs | ||
| linux | ||
| package | ||
| support | ||
| system | ||
| toolchain | ||
| .defconfig | ||
| .gitignore | ||
| CHANGES | ||
| Config.in | ||
| Config.in.legacy | ||
| COPYING | ||
| Makefile | ||
| Makefile.legacy | ||
| README | ||
Buildroot is a simple, efficient and easy-to-use tool to generate embedded Linux systems through cross-compilation. The documentation can be found in docs/manual. You can generate a text document with 'make manual-text' and read output/docs/manual/manual.text. Online documentation can be found at http://buildroot.org/docs.html To build and use the buildroot stuff, do the following: 1) run 'make menuconfig' 2) select the target architecture and the packages you wish to compile 3) run 'make' 4) wait while it compiles 5) find the kernel, bootloader, root filesystem, etc. in output/images You do not need to be root to build or run buildroot. Have fun! Buildroot comes with a basic configuration for a number of boards. Run 'make list-defconfigs' to view the list of provided configurations. Please feed suggestions, bug reports, insults, and bribes back to the buildroot mailing list: buildroot@buildroot.org You can also find us on #buildroot on Freenode IRC. If you would like to contribute patches, please read https://buildroot.org/manual.html#submitting-patches