[Qemu-devel] [patch] Add spare checker support to the build system

[Qemu-devel] [patch] Add spare checker support to the build system

[Gerd Hoffmann]

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  Hi,

This adds support for running the sparse checker during the build
process.  Left it off by default for now, build becomes very noisy with
sparse checking turned on as it has to complain alot (partly even in the
system headers!).  The qemu code base needs quite some cleanups before
we should consider turning it on by default.

please apply,
  Gerd

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>From aa926354ee308d46fdbb92667b6ed6f6f9b11ce7 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue, 7 Oct 2008 11:22:11 +0200
Subject: [PATCH] build system: sparse checker support.


Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 configure |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/configure b/configure
index 9c8ed81..5b23b33 100755
--- a/configure
+++ b/configure
@@ -85,6 +85,7 @@ case "$cpu" in
   ;;
 esac
 gprof="no"
+sparse="no"
 bigendian="no"
 mingw32="no"
 EXESUF=""
@@ -286,6 +287,10 @@ for opt do
   ;;
   --audio-drv-list=*) audio_drv_list="$optarg"
   ;;
+  --enable-sparse) sparse="yes"
+  ;;
+  --disable-sparse) sparse="no"
+  ;;
   --disable-vnc-tls) vnc_tls="no"
   ;;
   --disable-slirp) slirp="no"
@@ -425,6 +430,7 @@ echo "  --host-cc=CC             use C compiler CC [$host_cc] for dyngen etc."
 echo "  --make=MAKE              use specified make [$make]"
 echo "  --install=INSTALL        use specified install [$install]"
 echo "  --static                 enable static build [$static]"
+echo "  --disable-sparse         disable sparse checker"
 echo "  --disable-werror         disable compilation abort on warning"
 echo "  --disable-sdl            disable SDL"
 echo "  --enable-cocoa           enable COCOA (Mac OS X only)"
@@ -536,6 +542,10 @@ EOF
     fi
 fi
 
+if test ! -x "$(which cgcc 2>/dev/null)"; then
+    sparse="no"
+fi
+
 #
 # Solaris specific configure tool chain decisions
 #
@@ -1007,6 +1017,7 @@ echo "host CPU          $cpu"
 echo "host big endian   $bigendian"
 echo "target list       $target_list"
 echo "gprof enabled     $gprof"
+echo "sparse enabled    $sparse"
 echo "profiler          $profiler"
 echo "static build      $static"
 echo "-Werror enabled   $werror"
@@ -1156,6 +1167,11 @@ case "$cpu" in
     exit 1
   ;;
 esac
+if test "$sparse" = "yes" ; then
+  echo "CC      := REAL_CC=\"\$(CC)\" cgcc"       >> $config_mak
+  echo "HOST_CC := REAL_CC=\"\$(HOST_CC)\" cgcc"  >> $config_mak
+  echo "CFLAGS  += -Wbitwise -Wno-transparent-union -Wno-old-initializer -Wno-non-pointer-null" >> $config_mak
+fi
 if test "$bigendian" = "yes" ; then
   echo "WORDS_BIGENDIAN=yes" >> $config_mak
   echo "#define WORDS_BIGENDIAN 1" >> $config_h
-- 
1.5.5.1

Re: [Qemu-devel] [patch] Add spare checker support to the build system

[Anthony Liguori]

Gerd Hoffmann wrote:
>   Hi,
>
> This adds support for running the sparse checker during the build
> process.  Left it off by default for now, build becomes very noisy with
> sparse checking turned on as it has to complain alot (partly even in the
> system headers!).  The qemu code base needs quite some cleanups before
> we should consider turning it on by default.
>   

Applied.  Thanks.

You're missing a help description for --enable-sparse.  Could you please 
send a new patch adding that?

Regards,

Anthony Liguori

> please apply,
>   Gerd
>   

Re: [Qemu-devel] [patch] Add spare checker support to the build system

[Blue Swirl]

On 10/7/08, Gerd Hoffmann <kraxel@redhat.com> wrote:
>   Hi,
>
>  This adds support for running the sparse checker during the build
>  process.  Left it off by default for now, build becomes very noisy with
>  sparse checking turned on as it has to complain alot (partly even in the
>  system headers!).  The qemu code base needs quite some cleanups before
>  we should consider turning it on by default.

Cool, with sparse, I found and fixed one real bug and found one
missing 'static' just in target-sparc.

The cgcc test should try compiling a program like the C compiler test.
Maybe those tests could be merged?

Re: [Qemu-devel] [patch] Add spare checker support to the build system

[Anthony Liguori]

Blue Swirl wrote:
> On 10/7/08, Gerd Hoffmann <kraxel@redhat.com> wrote:
>   
>>   Hi,
>>
>>  This adds support for running the sparse checker during the build
>>  process.  Left it off by default for now, build becomes very noisy with
>>  sparse checking turned on as it has to complain alot (partly even in the
>>  system headers!).  The qemu code base needs quite some cleanups before
>>  we should consider turning it on by default.
>>     
>
> Cool, with sparse, I found and fixed one real bug and found one
> missing 'static' just in target-sparc.
>
> The cgcc test should try compiling a program like the C compiler test.
> Maybe those tests could be merged?
>   

It should if we're enabling it by default.  Since we don't enable it by 
default, presumably the user has a working version of sparse.

Also, to enable it by default, we need to think about how it interacts 
with cross compilers and other versions of GCC other than the default gcc.

Regards,

Anthony Liguori

Re: [Qemu-devel] [patch] Add spare checker support to the build system

[Gerd Hoffmann]

Blue Swirl wrote:
> Cool, with sparse, I found and fixed one real bug and found one
> missing 'static' just in target-sparc.

Great it proved being useful that quickly ;)

> The cgcc test should try compiling a program like the C compiler test.
> Maybe those tests could be merged?

cgcc isn't a compiler, it's a wrapper which runs both the real compiler
and the sparse checker, roughly comparable to distcc and ccache.  So if
$CC works, cgcc should too.

cheers,
  Gerd

Re: [Qemu-devel] [patch] Add spare checker support to the build system

[Gerd Hoffmann]

  Hi,

> Also, to enable it by default, we need to think about how it interacts
> with cross compilers and other versions of GCC other than the default gcc.

Oh, cross builds are supposed to work just fine with sparse enabled.

cheers,
  Gerd