[PATCH] make shadow code compile ok on FC4 which is using gcc4

[PATCH] make shadow code compile ok on FC4 which is using gcc4

[Li, Xin B]

We need this patch to make shadow code compile ok on FC4 which is using
gcc4.
-Xin

Signed-off-by: Xin Li <xin.b.li@intel.com>

diff -r a29b4174d39c xen/arch/x86/shadow.c
--- a/xen/arch/x86/shadow.c     Mon Jul 11 10:23:19 2005
+++ b/xen/arch/x86/shadow.c     Mon Jul 11 20:19:03 2005
@@ -2623,7 +2623,7 @@
     struct vcpu *v = current;
     struct domain *d = v->domain;
     pgentry_64_t sle;
-    pgentry_64_t sle_up;
+    pgentry_64_t sle_up = {0};
     l1_pgentry_t old_spte;
     l1_pgentry_t sl1e = *(l1_pgentry_t *)sl1e_p;
     int i;
diff -r a29b4174d39c xen/include/asm-x86/shadow_64.h
--- a/xen/include/asm-x86/shadow_64.h   Mon Jul 11 10:23:19 2005
+++ b/xen/include/asm-x86/shadow_64.h   Mon Jul 11 20:19:03 2005
@@ -485,8 +485,8 @@
 static inline unsigned long gva_to_gpa(unsigned long gva)
 {
     struct vcpu *v = current;
-    pgentry_64_t gl1e;
-    pgentry_64_t gl2e;
+    pgentry_64_t gl1e = {0};
+    pgentry_64_t gl2e = {0};
     unsigned long gpa;

     if (guest_page_fault(v, gva, 0, &gl2e, &gl1e))

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[David Hopwood]

Li, Xin B wrote:
> We need this patch to make shadow code compile ok on FC4 which is using
> gcc4.

Given gcc4's propensity to warn about things that are often harmless, is it
still a good idea to be compiling with -Werror?

-- 
David Hopwood <david.nospam.hopwood@blueyonder.co.uk>

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[Keir Fraser]

On 11 Jul 2005, at 20:19, David Hopwood wrote:

>> We need this patch to make shadow code compile ok on FC4 which is 
>> using
>> gcc4.
>
> Given gcc4's propensity to warn about things that are often harmless, 
> is it
> still a good idea to be compiling with -Werror?

It's been slightly annoying but not too much of a pain to keep things 
working with gcc4, and using -Werror does mean that genuine warnings 
don't get lost in the noise.

Anyway, we have more serious problems with gcc4 (I can't boot dom0 as 
far as a login prompt when I build xen+xenlinux with gcc4). Currently 
gcc 3.2.x and 3.3.x are the main supported compilers.

  -- Keir

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[Jerone Young]

On Mon, 2005-07-11 at 20:58 +0100, Keir Fraser wrote:
> On 11 Jul 2005, at 20:19, David Hopwood wrote:
> 
> >> We need this patch to make shadow code compile ok on FC4 which is 
> >> using
> >> gcc4.
> >
> > Given gcc4's propensity to warn about things that are often harmless, 
> > is it
> > still a good idea to be compiling with -Werror?
> 
> It's been slightly annoying but not too much of a pain to keep things 
> working with gcc4, and using -Werror does mean that genuine warnings 
> don't get lost in the noise.
> 
> Anyway, we have more serious problems with gcc4 (I can't boot dom0 as 
> far as a login prompt when I build xen+xenlinux with gcc4). Currently 
> gcc 3.2.x and 3.3.x are the main supported compilers.

That's odd. I'm booting and running xen+xenlinux fine with gcc4 under
FC4...with the 2.6.12 patch ...under x86-64 no less.

> 
>   -- Keir
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel
> 
-- 
Jerone Young
IBM Linux Technology Center
jyoung5@us.ibm.com
512-838-1157 (T/L: 678-1157)

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[Keir Fraser]

On 11 Jul 2005, at 21:11, Jerone Young wrote:

>> Anyway, we have more serious problems with gcc4 (I can't boot dom0 as
>> far as a login prompt when I build xen+xenlinux with gcc4). Currently
>> gcc 3.2.x and 3.3.x are the main supported compilers.
>
> That's odd. I'm booting and running xen+xenlinux fine with gcc4 under
> FC4...with the 2.6.12 patch ...under x86-64 no less.

It's a while since I tried (maybe a couple of months) so maybe the 
problems have gone away. Or perhaps it depends on the specific gcc4 
version you use -- I used vanilla 4.0.0, with no vendor patches.

  -- Keir

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[Rik van Riel]

On Mon, 11 Jul 2005, David Hopwood wrote:
> Li, Xin B wrote:
> > We need this patch to make shadow code compile ok on FC4 which is using
> > gcc4.
> 
> Given gcc4's propensity to warn about things that are often harmless, is 
> it still a good idea to be compiling with -Werror?

Fixing a compile warning is very little effort, but hunting
the occasional (1 in 50?) real bug can be extremely time
consuming.

I certainly don't mind fixing an error when I run into one...

-- 
The Theory of Escalating Commitment: "The cost of continuing mistakes is
borne by others, while the cost of admitting mistakes is borne by yourself."
  -- Joseph Stiglitz, Nobel Laureate in Economics

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[David Hopwood]

Rik van Riel wrote:
> On Mon, 11 Jul 2005, David Hopwood wrote:
>>Li, Xin B wrote:
>>
>>>We need this patch to make shadow code compile ok on FC4 which is using
>>>gcc4.
>>
>>Given gcc4's propensity to warn about things that are often harmless, is 
>>it still a good idea to be compiling with -Werror?
> 
> Fixing a compile warning is very little effort, but hunting
> the occasional (1 in 50?) real bug can be extremely time
> consuming.

I'm not suggesting that compiler warnings shouldn't be fixed; I'm suggesting
that they shouldn't break the build.

-- 
David Hopwood <david.nospam.hopwood@blueyonder.co.uk>

Re: [PATCH] make shadow code compile ok on FC4 which is using gcc4

[Rik van Riel]

On Tue, 12 Jul 2005, David Hopwood wrote:

> I'm not suggesting that compiler warnings shouldn't be fixed; I'm 
> suggesting that they shouldn't break the build.

My experience is they won't get fixed unless they break
something ;)

-- 
The Theory of Escalating Commitment: "The cost of continuing mistakes is
borne by others, while the cost of admitting mistakes is borne by yourself."
  -- Joseph Stiglitz, Nobel Laureate in Economics