projects / thirdparty / gcc.git / blame
| Commit | Line | Data |
|---|---|---|
| 0f3e711e JJ |
1 | dnl ---------------------------------------------------------------------- |
| 2 | dnl This whole bit snagged from libgomp. | |
| 3 | ||
| 4 | dnl | |
| 5 | dnl GCC_LINUX_FUTEX | |
| 6 | dnl (SHELL-CODE_HANDLER) | |
| 7 | dnl | |
| 8 | AC_DEFUN([GCC_LINUX_FUTEX],[dnl | |
| 9 | GCC_ENABLE(linux-futex,default, ,[use the Linux futex system call], | |
| 10 | permit yes|no|default) | |
| 11 | case "$target" in | |
| b1e21e5a | 12 | *-linux* | *-uclinux*) |
| 0f3e711e JJ |
13 | case "$enable_linux_futex" in |
| 14 | default) | |
| 15 | # If headers don't have gettid/futex syscalls definition, then | |
| 16 | # default to no, otherwise there will be compile time failures. | |
| 17 | # Otherwise, default to yes. If we don't detect we are | |
| 18 | # compiled/linked against NPTL and not cross-compiling, check | |
| 19 | # if programs are run by default against NPTL and if not, issue | |
| 20 | # a warning. | |
| 21 | enable_linux_futex=no | |
| 22 | AC_LINK_IFELSE( | |
| 23 | [AC_LANG_PROGRAM( | |
| 24 | [#include <sys/syscall.h> | |
| 3c086f8d | 25 | #include <unistd.h> |
| 0f3e711e JJ |
26 | int lk;], |
| 27 | [syscall (SYS_gettid); syscall (SYS_futex, &lk, 0, 0, 0);])], | |
| 28 | [save_LIBS="$LIBS" | |
| 29 | LIBS="-lpthread $LIBS" | |
| 30 | AC_LINK_IFELSE( | |
| 31 | [AC_LANG_PROGRAM( | |
| 32 | [#ifndef _GNU_SOURCE | |
| 33 | #define _GNU_SOURCE 1 | |
| 34 | #endif | |
| 35 | #include <pthread.h> | |
| 36 | pthread_t th; void *status;], | |
| 37 | [pthread_tryjoin_np (th, &status);])],[enable_linux_futex=yes], | |
| 38 | [if test x$cross_compiling = xno; then | |
| 39 | if getconf GNU_LIBPTHREAD_VERSION 2>/dev/null \ | |
| 40 | | LC_ALL=C grep -i NPTL > /dev/null 2>/dev/null; then :; else | |
| 41 | AC_MSG_WARN([The kernel might not support futex or gettid syscalls. | |
| 42 | If so, please configure with --disable-linux-futex]) | |
| 43 | fi | |
| 44 | fi | |
| 45 | enable_linux_futex=yes]) | |
| 46 | LIBS="$save_LIBS"]) | |
| 47 | ;; | |
| 48 | yes) | |
| 49 | AC_LINK_IFELSE( | |
| 50 | [AC_LANG_PROGRAM( | |
| 51 | [#include <sys/syscall.h> | |
| 3c086f8d | 52 | #include <unistd.h> |
| 0f3e711e JJ |
53 | int lk;], |
| 54 | [syscall (SYS_gettid); syscall (SYS_futex, &lk, 0, 0, 0);])],[], | |
| 55 | [AC_MSG_ERROR([SYS_gettid and SYS_futex required for --enable-linux-futex])]) | |
| 56 | ;; | |
| 57 | esac | |
| 58 | ;; | |
| 59 | *) | |
| 60 | enable_linux_futex=no | |
| 61 | ;; | |
| 62 | esac | |
| 63 | if test x$enable_linux_futex = xyes; then | |
| 64 | $1 | |
| 65 | fi | |
| 66 | ]) |