"Carlo Marcelo Arenas Belón via GitGitGadget" <gitgitgadget@xxxxxxxxx> writes: > +AC_CACHE_CHECK([whether SA_RESTART is supported], [ac_cv_siginterrupt], [ > + AC_COMPILE_IFELSE( > + [AC_LANG_PROGRAM([#include <signal.h>], [[ > + #ifdef SA_RESTART > + restartable signals supported > + #endif So, where SA_RESTART is defined, we fail the compilation. > + ]])],[ > + ac_cv_siginterrupt=no > + NO_RESTARTABLE_SIGNALS=UnfortunatelyYes As this is IFELSE, we know the condition that did not fail the compilation is where we did not see SA_RESTART. So we set the NO_RESTARTABLE_SIGNALS=UnfortunatelyYes, which makes sense. > + ], [ac_cv_siginterrupt=yes] > + ) > +]) > +GIT_CONF_SUBST([NO_RESTARTABLE_SIGNALS]) It is curious that throughout the two renames, the cached variable used by autoconf hasn't changed its name. Is it because it is totally invisible to the end-users/builders?
