Document minimum supported compiler versions

Pick some fairly old versions of clang and gcc and document them
as the minimum supported version.  This will let us make assumptions
about compiler features that are available when using those compilers.

Change-Id: Ibb8df72c9b12cc7adff39ece9708a428975ba703
Reviewed-on: https://gerrit.openafs.org/12331
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Mark Vitale <mvitale@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>

diff --git a/INSTALL b/INSTALL
index d2b4cf6..665e306 100644 (file)
--- a/INSTALL
+++ b/INSTALL
@@ -506,7 +506,9 @@ I  Other configure options
    CC
        The C compiler to use.  Be aware that this is overridden on some
        architectures that require a specific compiler be used to build the
-       kernel module.
+       kernel module.  If gcc is used, version 3 or later is required.
+       If clang is used, version 3 or later is required.  (Additional
+       restrictions apply when --enable-checking is used.)
 
    CFLAGS
        Additional flags to pass to the C compiler.