As both C and C++ standards require applications running under an OS to
return 'int', adapt that for Zephyr to align with those standard. This also
eliminates errors when building with clang when not using -ffreestanding,
and reduces the need for compiler flags to silence warnings for both clang
and gcc.
Signed-off-by: Keith Packard <keithp@keithp.com>
We weren't explicit about what we mean by "C++ support" as it relates
to standards versions, and it's been causing some friction in the tree
vs. some of our cruftier toolchains. Add a paragraph to clarify
things.
Fixes#55204
Signed-off-by: Andy Ross <andyross@google.com>
This describes the capabilities offered by Picolibc along with some of the
requirements applications have when using it.
Signed-off-by: Keith Packard <keithp@keithp.com>
This commit improves the C++ standard library documentation by adding
the list of supported C++ standard libraries.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
This commit reworks the C++ standard library configurations such that:
* the separation between the Zephyr minimal C++ library and the fully
featured C++ standard libraries, such as GNU libstdc++, is clear.
This is done by deprecating the Kconfig `CONFIG_LIB_CPLUSPLUS`
symbol, which implies that the minimal C++ library is selected when
set to `n`, and introducing the `CONFIG_MINIMAL_LIBCPP` symbol.
* the type of the selected C++ standard library is clear. This is done
by introducing a Kconfig choice, `LIBCPP_IMPLEMENTATION`, for the C++
standard library type and providing the choice symbols for each
library type supported, such as `CONFIG_MINIMAL_LIBCPP` and
`CONFIG_GLIBCXX_LIBCPP`.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
This commit updates all in-tree code to use `CONFIG_CPP_EXCEPTIONS`
instead of `CONFIG_EXCEPTIONS`, which is now deprecated.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
This commit updates all in-tree code to use `CONFIG_CPP` instead of
`CONFIG_CPLUSPLUS`, which is now deprecated.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
This commit moves the files under `subsys/cpp` directory to the
`lib/cpp` directory because the C++ ABI runtime library and the
standard C++ library components are not a "subsystem" (aka. API) in
conventional sense and is better described as a "library."
Classifying the C++ ABI runtime library and the standard C++ library as
"libraries" instead of "subsystems" also better aligns with how the
existing C standard library implementation (`lib/libc`) is handled.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
This commit adds notes about the C++ main() function prototype in the
C++ documentation.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
The newlib nano variant is currently enabled by default when
`CONFIG_NEWLIB_LIBC=y` and the selected toolchain-architecture
combination includes the newlib nano variant support, even if
`CONFIG_NEWLIB_LIBC_NANO` is not selected by the user.
When `CONFIG_NEWLIB_LIBC=y`, this results in the newlib nano variant
being selected for some architectures (e.g. ARC, ARM and RISC-V), while
the full variant is selected for the rest of the architectures.
The above behaviour is problematic because there exist functional
differences between the newlib full and nano variants (e.g. C99 format
modifiers such as `hh`, `ll`, `z`, `j` and `t` are not available in the
newlib nano variant), and this effectively leads to different level of
C standard support across different architectures when
`CONFIG_NEWLIB_LIBC=y`.
This commit fixes this problem by making the `CONFIG_NEWLIB_LIBC_NANO`
not `default y` and requiring its user to explicitly set this symbol to
`y` when they want to use the newlib nano variant.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
This commit adds "Formatted Output" section to the "C Language Support"
documentation that describes the C library-specific formatted output
support details.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit adds the sections describing how the dynamic memory
management is handled to the C language support and standard library
documentations.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit reworks the C++ language support documentation such that:
1. it contains more up-to-date information regarding the available
features.
2. it makes a clear distinction between the Zephyr C++ subsystem and
the C++ standard library and describe the functionalities they
provide.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit reworks the C language support documentation such that it
is more up to date and contains more information about the Newlib.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit adds the 'Language Support' sub-category under the
'Developing with Zephyr' category with programming language support-
related documentations.
The contents of the 'C standard library' page have been relocated to
the 'C Language Support' page, and the contents of the 'C++ Support for
Applications' page have been relocated to the 'C++ Language Support'
page.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
