[Bug c++/23959] New: -Wswitch-default reports missing default in a template that has one

[rlibiez at arthmoor dot com]

-Wswitch default warning flag is producing a warning message saying that a
template does not have a default case even though it does.

GCC version specs:

Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-libgcj-multifile
--enable-languages=c,c++,objc,java,f95,ada --enable-java-awt=gtk
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --host=i386-redhat-linux
Thread model: posix
gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)

Installed via RPM package from Fedora Core 4

Command line: g++ -o test test.c -Wswitch-default -Wall --pedantic

Compiler output:
test.c: In function 'void foo(ArrayType*)':
test.c:12: warning: switch missing default case

Detailed output:
g++ -v -save-temps -Wswitch-default -Wall --pedantic -o test test.c

Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-libgcj-multifile
--enable-languages=c,c++,objc,java,f95,ada --enable-java-awt=gtk
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --host=i386-redhat-linux
Thread model: posix
gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)
 /usr/libexec/gcc/i386-redhat-linux/4.0.1/cc1plus -E -quiet -v -D_GNU_SOURCE
test.c -Wswitch-default -Wall -pedantic -fpch-preprocess -o test.ii
ignoring nonexistent directory
"/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../../i386-redhat-linux/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/gcc/i386-redhat-linux/4.0.1/../../../../include/c++/4.0.1
 /usr/lib/gcc/i386-redhat-linux/4.0.1/../../../../include/c++/4.0.1/i386-redhat-linux
 /usr/lib/gcc/i386-redhat-linux/4.0.1/../../../../include/c++/4.0.1/backward
 /usr/local/include
 /usr/lib/gcc/i386-redhat-linux/4.0.1/include
 /usr/include
End of search list.
 /usr/libexec/gcc/i386-redhat-linux/4.0.1/cc1plus -fpreprocessed test.ii -quiet
-dumpbase test.c -auxbase test -Wswitch-default -Wall -pedantic -version -o test.s
GNU C++ version 4.0.1 20050727 (Red Hat 4.0.1-5) (i386-redhat-linux)
        compiled by GNU C version 4.0.1 20050727 (Red Hat 4.0.1-5).
GGC heuristics: --param ggc-min-expand=81 --param ggc-min-heapsize=96921
test.c: In function 'void foo(ArrayType*)':
test.c:12: warning: switch missing default case
 as -V -Qy -o test.o test.s
GNU assembler version 2.15.94.0.2.2 (i386-redhat-linux) using BFD version
2.15.94.0.2.2 20041220
 /usr/libexec/gcc/i386-redhat-linux/4.0.1/collect2 --eh-frame-hdr -m elf_i386
-dynamic-linker /lib/ld-linux.so.2 -o test
/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../crt1.o
/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../crti.o
/usr/lib/gcc/i386-redhat-linux/4.0.1/crtbegin.o
-L/usr/lib/gcc/i386-redhat-linux/4.0.1 -L/usr/lib/gcc/i386-redhat-linux/4.0.1
-L/usr/lib/gcc/i386-redhat-linux/4.0.1/../../.. test.o -lstdc++ -lm -lgcc_s
-lgcc -lc -lgcc_s -lgcc /usr/lib/gcc/i386-redhat-linux/4.0.1/crtend.o
/usr/lib/gcc/i386-redhat-linux/4.0.1/../../../crtn.o

Testcase code:

#include <iostream>

using namespace std;

template <typename ArrayType>
void foo( ArrayType * arr )
{
    int i = 0;

    for ( ;; )
    {
        switch ( arr[i] )
        {
            default:
                cout << arr[i] << endl;
                break;

            case 1:
            case 2:
            case 3:
            case 4:
            case 5:
            case 6:
            case 7:
            case 8:
            case 9:
                cout << "woot" << endl;
                continue;
        }

        i++;
    }
}

int main()
{
    int arr[10] = {1,2,3,4,5,6,7,8,9,10};

    foo<int>(arr);

    return 0;
}

-- 
           Summary: -Wswitch-default reports missing default in a template
                    that has one
           Product: gcc
           Version: 4.0.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rlibiez at arthmoor dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: Unknown
  GCC host triplet: Unknown
GCC target triplet: Unknown


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23959