[Qemu-devel] [PATCH v4 08/16] configure: Use -Wunused-const-variable

[Richard Henderson]

For the linux-user syscall split, we have static const structs
that must be matched up with a switch statement that uses them.
By default, gcc will not warn for such a variable, but silently
remove them.

For C++, such objects are sometimes declared for their constructor
side effects.  Do not propagate this flag into QEM_CXXFLAGS.

Signed-off-by: Richard Henderson <address@hidden>
---
 configure | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index db97930314..86e6e18428 100755
--- a/configure
+++ b/configure
@@ -105,7 +105,8 @@ update_cxxflags() {
     for arg in $QEMU_CFLAGS; do
         case $arg in
             -Wstrict-prototypes|-Wmissing-prototypes|-Wnested-externs|\
-            -Wold-style-declaration|-Wold-style-definition|-Wredundant-decls)
+            -Wold-style-declaration|-Wold-style-definition|-Wredundant-decls|\
+            -Wunused-const-variable)
                 ;;
             *)
                 QEMU_CXXFLAGS=${QEMU_CXXFLAGS:+$QEMU_CXXFLAGS }$arg
@@ -1780,6 +1781,7 @@ gcc_flags="-Wendif-labels -Wno-shift-negative-value 
$gcc_flags"
 gcc_flags="-Wno-initializer-overrides -Wexpansion-to-defined $gcc_flags"
 gcc_flags="-Wno-string-plus-int $gcc_flags"
 gcc_flags="-Wno-error=address-of-packed-member $gcc_flags"
+gcc_flags="-Wunused-const-variable $gcc_flags"
 # Note that we do not add -Werror to gcc_flags here, because that would
 # enable it for all configure tests. If a configure test failed due
 # to -Werror this would just silently disable some features,
-- 
2.17.1