New --enable-threading configure option to control use of threads in GDB/GDBserver

Add the --enable-threading configure option so multithreading can be disabled
at configure time. This is useful for statically-linked builds of
GDB/GDBserver, since the thread library doesn't play well with that setup.

If you try to run a statically-linked GDB built with threading, it will crash
when setting up the number of worker threads.

This new option is also convenient when debugging GDB in a system with lots of
threads, where the thread discovery code in GDB will emit too many messages,
like so:

[New Thread 0xfffff74d3a50 (LWP 2625599)]

If you have X threads, that message will be repeated X times.

The default for --enable-threading is "yes".

diff --git a/gdbserver/configure b/gdbserver/configure
index bcb15941ed127774fbfc7a354f68ccac0f77bf23..f72d9dd0ef647793b34d8475f877b1acf535de09 100755 (executable)
--- a/gdbserver/configure
+++ b/gdbserver/configure
@@ -7283,6 +7283,22 @@ else
 fi
 
 
+  # ----------------------- #
+  # Check for threading.    #
+  # ----------------------- #
+
+  # Check whether --enable-threading was given.
+if test "${enable_threading+set}" = set; then :
+  enableval=$enable_threading; case "$enableval" in
+    yes) want_threading=yes ;;
+    no) want_threading=no ;;
+    *) as_fn_error $? "bad value $enableval for threading" "$LINENO" 5 ;;
+    esac
+else
+  want_threading=yes
+fi
+
+
   # Check for std::thread.  This does not work on some platforms, like
   # mingw and DJGPP.
   ac_ext=cpp