From: Daniel P. Berrangé <berrange@redhat.com>
Date: Thu, 26 Jul 2018 14:47:23 +0000 (+0100)
Subject: conf: don't use virDomainVirtType in struct field
X-Git-Tag: v4.6.0-rc1~51
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9e66ecb5ea37fb12951934e3048c514b131657fe;p=thirdparty%2Flibvirt.git

conf: don't use virDomainVirtType in struct field

Use of enum types for struct fields is generally avoided since it causes
warnings if the compiler assumes the enum is unsigned. For example

  commit 8e2982b5767a25e5da6533c65bfdc648c95b3c69
  Author: Cole Robinson <crobinso@redhat.com>
  Date:   Tue Jul 24 16:27:54 2018 -0400

    conf: Clean up virDomainDefParseCaps

Introduced a line:

  if ((def->virtType = virDomainVirtTypeFromString(virttype)) < 0) {

which causes a build failure with CLang

  conf/domain_conf.c:19143:65: error: comparison of unsigned enum expression < 0 is always false [-Werror,-Wtautological-compare]

as the compiler is free to optimize away the "< 0" check due to the
assumption that the enum type is unsigned and always in range.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index c27c874d9e..f94a90fbcc 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -15075,7 +15075,7 @@ virDomainVideoDefaultRAM(const virDomainDef *def,
 int
 virDomainVideoDefaultType(const virDomainDef *def)
 {
-    switch (def->virtType) {
+    switch ((virDomainVirtType)def->virtType) {
     case VIR_DOMAIN_VIRT_TEST:
     case VIR_DOMAIN_VIRT_XEN:
         if (def->os.type == VIR_DOMAIN_OSTYPE_XEN ||
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index a804e86f6c..c1dfa37fdf 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -2386,7 +2386,7 @@ struct _virDomainVirtioOptions {
 typedef struct _virDomainDef virDomainDef;
 typedef virDomainDef *virDomainDefPtr;
 struct _virDomainDef {
-    virDomainVirtType virtType;
+    int virtType; /* enum virDomainVirtType */
     int id;
     unsigned char uuid[VIR_UUID_BUFLEN];
 
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index ae45c45b7f..d148db90fa 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -7163,7 +7163,7 @@ qemuBuildMachineCommandLine(virCommandPtr cmd,
     virCommandAddArg(cmd, "-machine");
     virBufferAdd(&buf, def->os.machine, -1);
 
-    switch (def->virtType) {
+    switch ((virDomainVirtType)def->virtType) {
     case VIR_DOMAIN_VIRT_QEMU:
         virBufferAddLit(&buf, ",accel=tcg");
         break;
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 27bd8b9465..c4e33723d1 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -7191,6 +7191,7 @@ int qemuProcessAttach(virConnectPtr conn ATTRIBUTE_UNUSED,
     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
     virCapsPtr caps = NULL;
     bool active = false;
+    virDomainVirtType virtType;
 
     VIR_DEBUG("Beginning VM attach process");
 
@@ -7342,8 +7343,9 @@ int qemuProcessAttach(virConnectPtr conn ATTRIBUTE_UNUSED,
         goto exit_monitor;
     if (qemuMonitorGetStatus(priv->mon, &running, &reason) < 0)
         goto exit_monitor;
-    if (qemuMonitorGetVirtType(priv->mon, &vm->def->virtType) < 0)
+    if (qemuMonitorGetVirtType(priv->mon, &virtType) < 0)
         goto exit_monitor;
+    vm->def->virtType = virtType;
     if (qemuDomainObjExitMonitor(driver, vm) < 0)
         goto error;