libbacktrace: Support the case that clock_gettime is in librt

	libbacktrace/
	PR other/67165
	* Makefile.am: Append the content of clock_gettime_link to
	ztest_LDADD.
	* configure.ac: Test for the case that clock_gettime is in librt.
	* Makefile.in: Regenerate.
	* configure: Likewise.

From-SVN: r253345

libbacktrace/ChangeLog

 2017-10-02  Thomas Schwinge  <thomas@codesourcery.com>
 
 	PR other/67165
+	* Makefile.am: Append the content of clock_gettime_link to
+	ztest_LDADD.
+	* configure.ac: Test for the case that clock_gettime is in librt.
+	* Makefile.in: Regenerate.
+	* configure: Likewise.
+
+	PR other/67165
 	* configure.ac: Check for clock_gettime.
 	* config.h.in: Regenerate.
 	* configure: Likewise.

libbacktrace/Makefile.am

@@ -108,6 +108,7 @@ ztest_LDADD = libbacktrace.la
 if HAVE_ZLIB
 ztest_LDADD += -lz
 endif
+ztest_LDADD += $(clock_gettime_link)
 
 check_PROGRAMS += ztest
 

libbacktrace/Makefile.in

@@ -165,7 +165,7 @@ ttest_LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
 @NATIVE_TRUE@	ztest-testlib.$(OBJEXT)
 ztest_OBJECTS = $(am_ztest_OBJECTS)
 @NATIVE_TRUE@ztest_DEPENDENCIES = libbacktrace.la \
-@NATIVE_TRUE@	$(am__DEPENDENCIES_1)
+@NATIVE_TRUE@	$(am__DEPENDENCIES_1) $(am__DEPENDENCIES_1)
 ztest_LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
 	--mode=link $(CCLD) $(ztest_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) \
 	$(LDFLAGS) -o $@
@@ -287,6 +287,7 @@ build_cpu = @build_cpu@
 build_os = @build_os@
 build_vendor = @build_vendor@
 builddir = @builddir@
+clock_gettime_link = @clock_gettime_link@
 datadir = @datadir@
 datarootdir = @datarootdir@
 docdir = @docdir@
@@ -383,7 +384,8 @@ TESTS = $(check_PROGRAMS) $(am__append_4)
 @NATIVE_TRUE@stest_LDADD = libbacktrace.la
 @NATIVE_TRUE@ztest_SOURCES = ztest.c testlib.c
 @NATIVE_TRUE@ztest_CFLAGS = -DSRCDIR=\"$(srcdir)\"
-@NATIVE_TRUE@ztest_LDADD = libbacktrace.la $(am__append_2)
+@NATIVE_TRUE@ztest_LDADD = libbacktrace.la $(am__append_2) \
+@NATIVE_TRUE@	$(clock_gettime_link)
 @NATIVE_TRUE@edtest_SOURCES = edtest.c edtest2_build.c testlib.c
 @NATIVE_TRUE@edtest_LDADD = libbacktrace.la
 @HAVE_PTHREAD_TRUE@@NATIVE_TRUE@ttest_SOURCES = ttest.c testlib.c

libbacktrace/configure

@@ -614,6 +614,7 @@ HAVE_ZLIB_TRUE
 HAVE_PTHREAD_FALSE
 HAVE_PTHREAD_TRUE
 PTHREAD_CFLAGS
+clock_gettime_link
 BACKTRACE_USES_MALLOC
 ALLOC_FILE
 VIEW_FILE
@@ -11145,7 +11146,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11148 "configure"
+#line 11149 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11251,7 +11252,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11254 "configure"
+#line 11255 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12759,6 +12760,57 @@ _ACEOF
 fi
 done
 
+clock_gettime_link=
+# At least for glibc, clock_gettime is in librt.  But don't
+# pull that in if it still doesn't give us the function we want.  This
+# test is copied from libgomp, and modified to not link in -lrt as
+# we're using this for test timing only.
+if test "$ac_cv_func_clock_gettime" = no; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for clock_gettime in -lrt" >&5
+$as_echo_n "checking for clock_gettime in -lrt... " >&6; }
+if test "${ac_cv_lib_rt_clock_gettime+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lrt  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char clock_gettime ();
+int
+main ()
+{
+return clock_gettime ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_rt_clock_gettime=yes
+else
+  ac_cv_lib_rt_clock_gettime=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_rt_clock_gettime" >&5
+$as_echo "$ac_cv_lib_rt_clock_gettime" >&6; }
+if test "x$ac_cv_lib_rt_clock_gettime" = x""yes; then :
+  clock_gettime_link=-lrt
+
+$as_echo "#define HAVE_CLOCK_GETTIME 1" >>confdefs.h
+
+fi
+
+fi
+
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -pthread is supported" >&5
 $as_echo_n "checking whether -pthread is supported... " >&6; }

libbacktrace/configure.ac

@@ -390,6 +390,18 @@ fi
 
 # Check for the clock_gettime function.
 AC_CHECK_FUNCS(clock_gettime)
+clock_gettime_link=
+# At least for glibc, clock_gettime is in librt.  But don't
+# pull that in if it still doesn't give us the function we want.  This
+# test is copied from libgomp, and modified to not link in -lrt as
+# we're using this for test timing only.
+if test "$ac_cv_func_clock_gettime" = no; then
+  AC_CHECK_LIB(rt, clock_gettime,
+    [clock_gettime_link=-lrt
+     AC_DEFINE(HAVE_CLOCK_GETTIME, 1,
+	       [Define to 1 if you have the `clock_gettime' function.])])
+fi
+AC_SUBST(clock_gettime_link)
 
 dnl Test whether the compiler supports the -pthread option.
 AC_CACHE_CHECK([whether -pthread is supported],