Fix warnings suppressors to honor --disable-werror

Replace

    #pragma GCC diagnostic ignored FOO
    [Troublesome code...]
    #pragma GCC diagnostic error FOO

by

    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored FOO
    [Troublesome code...]
    #pragma GCC diagnostic pop

Broken in commit 3f4349d, commit 092bb30, and commit c95e308.

Signed-off-by: Markus Armbruster <[email protected]>
Tested-by: Alexey Kardashevskiy <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
Message-id: [email protected]
Signed-off-by: Anthony Liguori <[email protected]>

configure

@@ -3268,8 +3268,10 @@ fi
 
 pragma_disable_unused_but_set=no
 cat > $TMPC << EOF
+#pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wunused-but-set-variable"
 #pragma GCC diagnostic ignored "-Wstrict-prototypes"
+#pragma GCC diagnostic pop
 
 int main(void) {
     return 0;

coroutine-ucontext.c

@@ -169,14 +169,15 @@ Coroutine *qemu_coroutine_new(void)
 #ifdef CONFIG_VALGRIND_H
 #ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
 /* Work around an unused variable in the valgrind.h macro... */
+#pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wunused-but-set-variable"
 #endif
 static inline void valgrind_stack_deregister(CoroutineUContext *co)
 {
     VALGRIND_STACK_DEREGISTER(co->valgrind_stack_id);
 }
 #ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
-#pragma GCC diagnostic error "-Wunused-but-set-variable"
+#pragma GCC diagnostic pop
 #endif
 #endif
 

include/ui/qemu-pixman.h

@@ -8,11 +8,12 @@
 
 /* pixman-0.16.0 headers have a redundant declaration */
 #ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
+#pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wredundant-decls"
 #endif
 #include <pixman.h>
 #ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
-#pragma GCC diagnostic error "-Wredundant-decls"
+#pragma GCC diagnostic pop
 #endif
 
 #include "qemu/typedefs.h"

ui/gtk.c

@@ -38,11 +38,12 @@
 
 #ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
 /* Work around an -Wstrict-prototypes warning in GTK headers */
+#pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wstrict-prototypes"
 #endif
 #include <gtk/gtk.h>
 #ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
-#pragma GCC diagnostic error "-Wstrict-prototypes"
+#pragma GCC diagnostic pop
 #endif