Prettify configure output when checking for backtrace().

The output of "checking for backtrace()" was interspersed with the output of
"checking for library containing backtrace", which was ugly and potentially
confusing, so move AC_SEARCH_LIBS() out of AC_CACHE_CHECK() to fix it.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78430 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

configure

@@ -30268,13 +30268,54 @@ _ACEOF
 fi
 
 if test "$wxUSE_STACKWALKER" = "yes" -a "$wxUSE_UNIX" = "yes"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for backtrace() in <execinfo.h>" >&5
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for backtrace()" >&5
-$as_echo_n "checking for backtrace() in <execinfo.h>... " >&6; }
+$as_echo_n "checking for backtrace()... " >&6; }
 if ${wx_cv_func_backtrace+:} false; then :
   $as_echo_n "(cached) " >&6
 else
 
-            { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing backtrace" >&5
+            ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+            cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <execinfo.h>
+int
+main ()
+{
+
+                    void *trace[1];
+                    char **messages;
+                    backtrace(trace, 1);
+                    messages = backtrace_symbols(trace, 1);
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+  wx_cv_func_backtrace=yes
+else
+  wx_cv_func_backtrace=no
+
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+            ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $wx_cv_func_backtrace" >&5
+$as_echo "$wx_cv_func_backtrace" >&6; }
+
+        { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing backtrace" >&5
 $as_echo_n "checking for library containing backtrace... " >&6; }
 if ${ac_cv_search_backtrace+:} false; then :
   $as_echo_n "(cached) " >&6
@@ -30328,54 +30369,11 @@ ac_res=$ac_cv_search_backtrace
 if test "$ac_res" != no; then :
   test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
 
-                    ac_ext=cpp
-ac_cpp='$CXXCPP $CPPFLAGS'
-ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
-
-                    cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <execinfo.h>
-int
-main ()
-{
-
-                            void *trace[1];
-                            char **messages;
-                            backtrace(trace, 1);
-                            messages = backtrace_symbols(trace, 1);
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_cxx_try_link "$LINENO"; then :
-  wx_cv_func_backtrace=yes
 else
   wx_cv_func_backtrace=no
-
-fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-                    ac_ext=c
-ac_cpp='$CPP $CPPFLAGS'
-ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
-ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
-ac_compiler_gnu=$ac_cv_c_compiler_gnu
-
-
-else
-  wx_cv_func_backtrace=no
-
 fi
 
 
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $wx_cv_func_backtrace" >&5
-$as_echo "$wx_cv_func_backtrace" >&6; }
-
     if test "$wx_cv_func_backtrace" = "no"; then
         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: backtrace() is not available, wxStackWalker will not be available" >&5
 $as_echo "$as_me: WARNING: backtrace() is not available, wxStackWalker will not be available" >&2;}

configure.in

@@ -4157,28 +4157,26 @@ fi
 
 dnl backtrace() and backtrace_symbols() for wxStackWalker
 if test "$wxUSE_STACKWALKER" = "yes" -a "$wxUSE_UNIX" = "yes"; then
-    AC_CACHE_CHECK([for backtrace() in <execinfo.h>], wx_cv_func_backtrace,
+    AC_CACHE_CHECK([for backtrace()], wx_cv_func_backtrace,
         [
-            AC_SEARCH_LIBS(backtrace, execinfo,
+            AC_LANG_PUSH(C++)
+            AC_TRY_COMPILE([#include <execinfo.h>],
                 [
-                    AC_LANG_PUSH(C++)
+                    void *trace[1];
-                    AC_TRY_LINK([#include <execinfo.h>],
+                    char **messages;
-                        [
+                    backtrace(trace, 1);
-                            void *trace[1];
+                    messages = backtrace_symbols(trace, 1);
-                            char **messages;
-                            backtrace(trace, 1);
-                            messages = backtrace_symbols(trace, 1);
-                        ],
-                        wx_cv_func_backtrace=yes,
-                        wx_cv_func_backtrace=no
-                    )
-                    AC_LANG_POP()
                 ],
+                wx_cv_func_backtrace=yes,
                 wx_cv_func_backtrace=no
             )
+            AC_LANG_POP()
         ]
     )
 
+    dnl Under BSD it can require linking with libexecinfo.
+    AC_SEARCH_LIBS(backtrace, execinfo, , [wx_cv_func_backtrace=no])
+
     if test "$wx_cv_func_backtrace" = "no"; then
         AC_MSG_WARN([backtrace() is not available, wxStackWalker will not be available])
         wxUSE_STACKWALKER=no