[Bug c/49859] New: gcc could warn about statements between "switch" and first "case"

[wkoszek at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49859

           Summary: gcc could warn about statements between "switch" and
                    first "case"
           Product: gcc
           Version: 4.5.2
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: wkoszek@gmail.com


Created attachment 24838
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24838
Sample source code.

wkoszek@wkoszek:~/p/switch$ cat switch.c 
#include <stdio.h>

int
main(int argc, char **argv)
{
    int    type;

    type = 123;
    switch (type) {
        printf("SOMETHING\n");
    case 1:
        printf("1\n");
        break;
    case 2:
        printf("2\n");
        break;
    default:
        printf("default\n");
        return 1;
    }
    return 0;
}
wkoszek@wkoszek:~/p/switch$ gcc -pedantic -Wall -Wunused -Wunreachable-code -c
switch.c
wkoszek@wkoszek:~/p/switch$ clang -pedantic -Wall -Wunused -Wunreachable-code
-c switch.c
switch.c:10:3: warning: will never be executed [-Wunreachable-code]
                printf("SOMETHING\n");
                ^~~~~~~~~~~~~~~~~~~~~
1 warning generated.


wkoszek@wkoszek:~/p/switch$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/i386-linux-gnu/gcc/i686-linux-gnu/4.5.2/lto-wrapper
Target: i686-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.5.2-8ubuntu4' --with-bugurl=file:///usr/share/doc/gcc-4.5/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-4.5 --enable-shared --enable-multiarch
--with-multiarch-defaults=i386-linux-gnu --enable-linker-build-id
--with-system-zlib --libexecdir=/usr/lib/i386-linux-gnu
--without-included-gettext --enable-threads=posix
--with-gxx-include-dir=/usr/include/c++/4.5 --libdir=/usr/lib/i386-linux-gnu
--enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug
--enable-libstdcxx-time=yes --enable-plugin --enable-gold --enable-ld=default
--with-plugin-ld=ld.gold --enable-objc-gc --enable-targets=all --disable-werror
--with-arch-32=i686 --with-tune=generic --enable-checking=release
--build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu
Thread model: posix
gcc version 4.5.2 (Ubuntu/Linaro 4.5.2-8ubuntu4)