maint: Fix macros with broken 'do/while(0); ' usage

The point of writing a macro embedded in a 'do { ... } while (0)'
loop (particularly if the macro has multiple statements or would
otherwise end with an 'if' statement) is so that the macro can be
used as a drop-in statement with the caller supplying the
trailing ';'.  Although our coding style frowns on brace-less 'if':
  if (cond)
    statement;
  else
    something else;
that is the classic case where failure to use do/while(0) wrapping
would cause the 'else' to pair with any embedded 'if' in the macro
rather than the intended outer 'if'.  But conversely, if the macro
includes an embedded ';', then the same brace-less coding style
would now have two statements, making the 'else' a syntax error
rather than pairing with the outer 'if'.  Thus, even though our
coding style with required braces is not impacted, ending a macro
with ';' makes our code harder to port to projects that use
brace-less styles.

The change should have no semantic impact.  I was not able to
fully compile-test all of the changes (as some of them are
examples of the ugly bit-rotting debug print statements that are
completely elided by default, and I didn't want to recompile
with the necessary -D witnesses - cleaning those up is left as a
bite-sized task for another day); I did, however, audit that for
all files touched, all callers of the changed macros DID supply
a trailing ';' at the callsite, and did not appear to be used
as part of a brace-less conditional.

Found mechanically via: $ git grep -B1 'while (0);' | grep -A1 \\\\

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20171201232433.25193-7-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

3 files changed, 3 insertions, 3 deletions

diff --git a/hw/display/cg3.c b/hw/display/cg3.c
index e069c4484c..cafd9f47ef 100644
--- a/hw/display/cg3.c
+++ b/hw/display/cg3.c
@@ -63,7 +63,7 @@
     if (DEBUG_CG3) { \
         printf("CG3: " fmt , ## __VA_ARGS__); \
     } \
-} while (0);
+} while (0)
 
 #define TYPE_CG3 "cgthree"
 #define CG3(obj) OBJECT_CHECK(CG3State, (obj), TYPE_CG3)
diff --git a/hw/display/dpcd.c b/hw/display/dpcd.c
index ce92ff6e2a..943002bee5 100644
--- a/hw/display/dpcd.c
+++ b/hw/display/dpcd.c
@@ -39,7 +39,7 @@
     if (DEBUG_DPCD) {                                                          \
         qemu_log("dpcd: " fmt, ## __VA_ARGS__);                                \
     }                                                                          \
-} while (0);
+} while (0)
 
 #define DPCD_READABLE_AREA                      0x600
 
diff --git a/hw/display/xlnx_dp.c b/hw/display/xlnx_dp.c
index 561f828e7a..ead4e1a0e4 100644
--- a/hw/display/xlnx_dp.c
+++ b/hw/display/xlnx_dp.c
@@ -34,7 +34,7 @@
     if (DEBUG_DP) {                                                            \
         qemu_log("xlnx_dp: " fmt , ## __VA_ARGS__);                            \
     }                                                                          \
-} while (0);
+} while (0)
 
 /*
  * Register offset for DP.