lkml.org 
[lkml]   [2011]   [Jul]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [PATCH] TRACING: Fix a copmile warning
    From
    Hi,

    On Mon, Jul 25, 2011 at 4:19 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
    > On Mon, 2011-07-25 at 15:43 -0400, Arnaud Lacombe wrote:
    >
    >> Actually, we have a special uninitialized_var(x) macro to handle such
    >> false positive. From include/linux/compiler-gcc.h:
    >>
    >> /*
    >>  * A trick to suppress uninitialized variable warning without generating any
    >>  * code
    >>  */
    >> #define uninitialized_var(x) x = x
    >
    > I'm aware of that too, but I think that is inappropriate as well. As I
    > said, some versions of gcc report it, others don't. Seems that gcc 4.6.0
    > says this is an error where 4.5.1 does not (I just tried both).
    >
    did you ? gcc 4.5.1 from Fedora 14 definitively shows the warning:

    # make ARCH=i386 kernel/trace/trace_printk.o V=1
    [...]
    gcc -Wp,-MD,kernel/trace/.trace_printk.o.d -nostdinc -isystem
    /usr/lib/gcc/x86_64-redhat-linux/4.5.1/include [...] -c -o
    kernel/trace/trace_printk.o kernel/trace/trace_printk.c
    /src/linux/linux/kernel/trace/trace_printk.c: In function
    'hold_module_trace_bprintk_format':
    /src/linux/linux/kernel/trace/trace_printk.c:52:8: warning: 'fmt' may
    be used uninitialized in this function

    # gcc -v
    gcc -v
    Using built-in specs.
    COLLECT_GCC=gcc
    COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/4.5.1/lto-wrapper
    Target: x86_64-redhat-linux
    Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
    --infodir=/usr/share/info
    --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap
    --enable-shared --enable-threads=posix --enable-checking=release
    --with-system-zlib --enable-__cxa_atexit
    --disable-libunwind-exceptions --enable-gnu-unique-object
    --enable-linker-build-id
    --enable-languages=c,c++,objc,obj-c++,java,fortran,ada,lto
    --enable-plugin --enable-java-awt=gtk --disable-dssi
    --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre
    --enable-libgcj-multifile --enable-java-maintainer-mode
    --with-ecj-jar=/usr/share/java/eclipse-ecj.jar
    --disable-libjava-multilib --with-ppl --with-cloog --with-tune=generic
    --with-arch_32=i686 --build=x86_64-redhat-linux
    Thread model: posix
    gcc version 4.5.1 20100924 (Red Hat 4.5.1-4) (GCC)

    - Arnaud
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2011-07-26 00:41    [W:0.027 / U:91.744 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site