configure: Disable -Wtautological-type-limit-compare

Clang 10 enables this by default with -Wtype-limit.

All of the instances flagged by this Werror so far have been
cases in which we really do want the compiler to optimize away
the test completely.  Disabling the warning will avoid having
to add ifdefs to work around this.

Cc: Eric Blake <eblake@redhat.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1878628
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200617201309.1640952-5-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/configure b/configure
index a8bef952820f52483338244f2c84ca72aa5c9794..5e27229f58a31d970c0f732b45cb06a237f564df 100755 (executable)
--- a/configure
+++ b/configure
@@ -2054,6 +2054,7 @@ add_to nowarn_flags -Wno-missing-include-dirs
 add_to nowarn_flags -Wno-shift-negative-value
 add_to nowarn_flags -Wno-string-plus-int
 add_to nowarn_flags -Wno-typedef-redefinition
+add_to nowarn_flags -Wno-tautological-type-limit-compare
 
 gcc_flags="$warn_flags $nowarn_flags"