diff --git a/doc/building.html b/doc/building.html
index d51e74d1454..96d2916de41 100644
--- a/doc/building.html
+++ b/doc/building.html
@@ -2166,15 +2166,26 @@ you can create a directory under <code>build</code> and run
 <code>configure</code> from there, e.g.
 <code>mkdir build/&lt;name&gt; &amp;&amp; cd build/&lt;name&gt; &amp;&amp; bash ../../configure</code>.</p>
 <p>Then you can build that configuration using
-<code>make CONF_NAME=&lt;name&gt;</code> or
-<code>make CONF=&lt;pattern&gt;</code>, where
-<code>&lt;pattern&gt;</code> is a substring matching one or several
-configurations, e.g. <code>CONF=debug</code>. The special empty pattern
-(<code>CONF=</code>) will match <em>all</em> available configuration, so
-<code>make CONF= hotspot</code> will build the <code>hotspot</code>
-target for all configurations. Alternatively, you can execute
-<code>make</code> in the configuration directory, e.g.
-<code>cd build/&lt;name&gt; &amp;&amp; make</code>.</p>
+<code>make CONF=&lt;selector&gt;</code>, where
+<code>&lt;selector&gt;</code> is interpreted as follows:</p>
+<ul>
+<li>If <code>&lt;selector&gt;</code> exacly matches the name of a
+configuration, this and only this configuration will be selected.</li>
+<li>If <code>&lt;selector&gt;</code> matches (i.e. is a substring of)
+the names of several configurations, then all these configurations will
+be selected.</li>
+<li>If <code>&lt;selector&gt;</code> is empty (i.e. <code>CONF=</code>),
+then all configurations will be selected.</li>
+<li>If <code>&lt;selector&gt;</code> begins with <code>!</code>, then
+all configurations <strong>not</strong> matching the string following
+<code>!</code> will be selected.</li>
+</ul>
+<p>A more specialized version, <code>CONF_NAME=&lt;name&gt;</code> also
+exists, which will only match if the given <code>&lt;name&gt;</code>
+exactly matches a single configuration.</p>
+<p>Alternatively, you can execute <code>make</code> in the configuration
+directory, e.g. <code>cd build/&lt;name&gt; &amp;&amp; make</code>.</p>
+<p><code>make CONF_NAME=&lt;name&gt;</code> or</p>
 <h3 id="handling-reconfigurations">Handling Reconfigurations</h3>
 <p>If you update the repository and part of the configure script has
 changed, the build system will force you to re-run
diff --git a/doc/building.md b/doc/building.md
index 9d928a39245..61daed2270b 100644
--- a/doc/building.md
+++ b/doc/building.md
@@ -1952,12 +1952,25 @@ configuration with the name `<name>`. Alternatively, you can create a directory
 under `build` and run `configure` from there, e.g. `mkdir build/<name> && cd
 build/<name> && bash ../../configure`.
 
-Then you can build that configuration using `make CONF_NAME=<name>` or `make
-CONF=<pattern>`, where `<pattern>` is a substring matching one or several
-configurations, e.g. `CONF=debug`. The special empty pattern (`CONF=`) will
-match *all* available configuration, so `make CONF= hotspot` will build the
-`hotspot` target for all configurations. Alternatively, you can execute `make`
-in the configuration directory, e.g. `cd build/<name> && make`.
+Then you can build that configuration using `make CONF=<selector>`, where
+`<selector>` is interpreted as follows:
+
+* If `<selector>` exacly matches the name of a configuration, this and only
+  this configuration will be selected.
+* If `<selector>` matches (i.e. is a substring of) the names of several
+  configurations, then all these configurations will be selected.
+* If `<selector>` is empty (i.e. `CONF=`), then all configurations will be
+  selected.
+* If `<selector>` begins with `!`, then all configurations **not** matching the
+  string following `!` will be selected.
+
+A more specialized version, `CONF_NAME=<name>` also exists, which will only
+match if the given `<name>` exactly matches a single configuration.
+
+Alternatively, you can execute `make` in the configuration directory, e.g. `cd
+build/<name> && make`.
+
+`make CONF_NAME=<name>` or
 
 ### Handling Reconfigurations
 
diff --git a/make/Global.gmk b/make/Global.gmk
index e5e76b475b9..1df6c5fb6bc 100644
--- a/make/Global.gmk
+++ b/make/Global.gmk
@@ -87,10 +87,9 @@ help:
 	$(info $(_)                        # (gensrc, java, copy, libs, launchers, gendata))
 	$(info )
 	$(info Make control variables)
-	$(info $(_) CONF=                  # Build all configurations (note, assignment is empty))
-	$(info $(_) CONF=<substring>       # Build the configuration(s) with a name matching)
-	$(info $(_)                        # <substring>)
-	$(info $(_) CONF_NAME=<string>     # Build the configuration with exactly the <string>)
+	$(info $(_) CONF=<selector>        # Select which configuration(s) to build)
+	$(info $(_) CONF=                  # Select all configurations (note, assignment is empty))
+	$(info $(_) CONF_NAME=<string>     # Select the configuration with the name <string>)
 	$(info $(_) SPEC=<spec file>       # Build the configuration given by the spec file)
 	$(info $(_) LOG=<loglevel>         # Change the log level from warn to <loglevel>)
 	$(info $(_)                        # Available log levels are:)
diff --git a/make/InitSupport.gmk b/make/InitSupport.gmk
index 31c80e2f726..9ea01d375ce 100644
--- a/make/InitSupport.gmk
+++ b/make/InitSupport.gmk
@@ -202,8 +202,14 @@ ifeq ($(HAS_SPEC),)
           matching_confs := $$(strip $$(all_confs))
         else
           # Otherwise select those that contain the given CONF string
-          matching_confs := $$(strip $$(foreach var, $$(all_confs), \
-              $$(if $$(findstring $$(CONF), $$(var)), $$(var))))
+          ifeq ($$(patsubst !%,,$$(CONF)),)
+            # A CONF starting with ! means we should negate the search term
+            matching_confs := $$(strip $$(foreach var, $$(all_confs), \
+               $$(if $$(findstring $$(subst !,,$$(CONF)), $$(var)), ,$$(var))))
+          else
+            matching_confs := $$(strip $$(foreach var, $$(all_confs), \
+                $$(if $$(findstring $$(CONF), $$(var)), $$(var))))
+          endif
           ifneq ($$(filter $$(CONF), $$(matching_confs)), )
             # If we found an exact match, use that
             matching_confs := $$(CONF)