The header file `ucontext.h` is not available on musl based distros. The example `ucontext-cp` is not built if `configure` fails to locate the header. Signed-off-by: Simon Zeni <simon@xxxxxxxxxxxx> --- See [this mail][1] from the musl mailing list about why those functions are not implemented I also noticed that `make runtests` fails on alpinelinux (5.4.72-0-lts with musl-1.2.1) ``` Tests failed: <accept-reuse> <across-fork> <defer> <double-poll-crash> <file-register> <file-update> <io_uring_enter> <io_uring_register> <lfs-openat> <lfs-openat-write> <link-timeout> <link_drain> <open-close> <openat2> <pipe-eof> <poll-cancel> <poll-cancel-ton> <poll-link> <read-write> <sigfd-deadlock> <sq-poll-dup> <sq-poll-share> <sq-space_left> <timeout> <statx> ``` I can post a full trace if needed. Simon [1]: https://www.openwall.com/lists/musl/2016/02/04/4 configure | 21 +++++++++++++++++++++ examples/Makefile | 6 +++++- 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/configure b/configure index c911f59..3b96cde 100755 --- a/configure +++ b/configure @@ -287,6 +287,24 @@ if compile_prog_cxx "" "" "C++"; then fi print_config "C++" "$has_cxx" +########################################## +# check for ucontext support +has_ucontext="no" +cat > $TMPC << EOF +#include <ucontext.h> +int main(int argc, char **argv) +{ + ucontext_t ctx; + getcontext(&ctx); + return 0; +} +EOF +if compile_prog "" "" "has_ucontext"; then + has_ucontext="yes" +fi +print_config "has_ucontext" "$has_ucontext" + + ############################################################################# if test "$__kernel_rwf_t" = "yes"; then @@ -304,6 +322,9 @@ fi if test "$has_cxx" = "yes"; then output_sym "CONFIG_HAVE_CXX" fi +if test "$has_ucontext" = "yes"; then + output_sym "CONFIG_HAVE_UCONTEXT" +fi echo "CC=$cc" >> $config_host_mak print_config "CC" "$cc" diff --git a/examples/Makefile b/examples/Makefile index 0eec627..60c1b71 100644 --- a/examples/Makefile +++ b/examples/Makefile @@ -10,7 +10,11 @@ ifneq ($(MAKECMDGOALS),clean) include ../config-host.mak endif -all_targets += io_uring-test io_uring-cp link-cp ucontext-cp +all_targets += io_uring-test io_uring-cp link-cp + +ifdef CONFIG_HAVE_UCONTEXT +all_targets += ucontext-cp +endif all: $(all_targets) -- 2.29.1
