8295229: Try to verify gtest version

Reviewed-by: erikj

doc/testing.html

@@ -92,6 +92,7 @@ $ make exploded-test TEST=tier2</code></pre>
 <p>Individual JTReg tests or directories containing JTReg tests can also be specified, like <code>test/hotspot/jtreg/native_sanity/JniVersion.java</code> or <code>hotspot/jtreg/native_sanity</code>. Just like for test root selection, you can either specify an absolute path (which can even point to JTReg tests outside the source tree), or a path relative to either the JDK top directory or the <code>test</code> directory. <code>hotspot</code> can be used as an alias for <code>hotspot/jtreg</code> here as well.</p>
 <p>As long as the test groups or test paths can be uniquely resolved, you do not need to enter the <code>jtreg:</code> prefix. If this is not possible, or if you want to use a fully qualified test descriptor, add <code>jtreg:</code>, e.g. <code>jtreg:test/hotspot/jtreg/native_sanity</code>.</p>
 <h3 id="gtest">Gtest</h3>
+<p><strong>Note:</strong> To be able to run the Gtest suite, you need to configure your build to be able to find a proper version of the gtest source. For details, see the section <a href="building.html#running-tests">&quot;Running Tests&quot; in the build documentation</a>.</p>
 <p>Since the Hotspot Gtest suite is so quick, the default is to run all tests. This is specified by just <code>gtest</code>, or as a fully qualified test descriptor <code>gtest:all</code>.</p>
 <p>If you want, you can single out an individual test or a group of tests, for instance <code>gtest:LogDecorations</code> or <code>gtest:LogDecorations.level_test_vm</code>. This can be particularly useful if you want to run a shaky test repeatedly.</p>
 <p>For Gtest, there is a separate test suite for each JVM variant. The JVM variant is defined by adding <code>/&lt;variant&gt;</code> to the test descriptor, e.g. <code>gtest:Log/client</code>. If you specify no variant, gtest will run once for each JVM variant present (e.g. server, client). So if you only have the server JVM present, then <code>gtest:all</code> will be equivalent to <code>gtest:all/server</code>.</p>

doc/testing.md

@@ -169,6 +169,11 @@ use a fully qualified test descriptor, add `jtreg:`, e.g.
 
 ### Gtest
 
+**Note:** To be able to run the Gtest suite, you need to configure your build to
+be able to find a proper version of the gtest source. For details, see the
+section ["Running Tests" in the build
+documentation](building.html#running-tests).
+
 Since the Hotspot Gtest suite is so quick, the default is to run all tests.
 This is specified by just `gtest`, or as a fully qualified test descriptor
 `gtest:all`.

make/autoconf/lib-tests.m4

@@ -54,9 +54,25 @@ AC_DEFUN_ONCE([LIB_TESTS_SETUP_GTEST],
         AC_MSG_RESULT([no])
         AC_MSG_ERROR([Can't find 'googlemock/include/gmock/gmock.h' under ${with_gtest} given with the --with-gtest option.])
       else
-        GTEST_FRAMEWORK_SRC=${with_gtest}
+        GTEST_FRAMEWORK_SRC=$with_gtest
         AC_MSG_RESULT([$GTEST_FRAMEWORK_SRC])
         UTIL_FIXUP_PATH([GTEST_FRAMEWORK_SRC])
+
+        # Try to verify version. We require 1.8.1, but this can not be directly
+        # determined. :-( Instead, there are different, incorrect version
+        # numbers we can look for.
+        GTEST_VERSION_1="`$GREP GOOGLETEST_VERSION $GTEST_FRAMEWORK_SRC/CMakeLists.txt | $SED -E -e 's/set\(GOOGLETEST_VERSION (.*)\)/\1/'`"
+        if test "x$GTEST_VERSION_1" != "x1.9.0"; then
+          AC_MSG_ERROR([gtest at $GTEST_FRAMEWORK_SRC does not seem to be version 1.8.1])
+        fi
+
+        # We cannot grep for "AC_IN*T" as a literal since then m4 will treat it as a macro
+        # and expand it.
+        # Additional [] needed to keep m4 from mangling shell constructs.
+        [ GTEST_VERSION_2="`$GREP -A1 ^.C_INIT $GTEST_FRAMEWORK_SRC/configure.ac | $TAIL -n 1 | $SED -E -e 's/ +\[(.*)],/\1/'`" ]
+        if test "x$GTEST_VERSION_2" != "x1.8.0"; then
+          AC_MSG_ERROR([gtest at $GTEST_FRAMEWORK_SRC does not seem to be version 1.8.1 B])
+        fi
       fi
     fi
   fi