| AC_DEFUN([LIBUNWIND___THREAD], |
| [dnl Check whether the compiler supports the __thread keyword. |
| if test "x$use__thread" != xno; then |
| AC_CACHE_CHECK([for __thread], libc_cv_gcc___thread, |
| [cat > conftest.c <<\EOF |
| __thread int a = 42; |
| EOF |
| if AC_TRY_COMMAND([${CC-cc} $CFLAGS -c conftest.c >&AS_MESSAGE_LOG_FD]); then |
| libc_cv_gcc___thread=yes |
| else |
| libc_cv_gcc___thread=no |
| fi |
| rm -f conftest*]) |
| if test "$libc_cv_gcc___thread" = yes; then |
| AC_DEFINE(HAVE___THREAD, 1, |
| [Define to 1 if __thread keyword is supported by the C compiler.]) |
| fi |
| else |
| libc_cv_gcc___thread=no |
| fi]) |