Created attachment 1244090 [details]
Test this code with "g++ test.cpp"

Hi,
The attached C++ code has been compiling fine since RHEL 5, and does not compile anymore under RHEL 7.3 using GCC 4.8.5.
The related bug (involving valarray, endl and <<) has been identified and fixed in GCC 4.9.4, 5.4 and 6.1: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69116

I would like to know if a backport to the 4.8 package is possible.

Thanks


# gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/4.8.5/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 --with-linker-hash-style=gnu --enable-languages=c,c++,objc,obj-c++,java,fortran,ada,go,lto --enable-plugin --enable-initfini-array --disable-libgcj --with-isl=/builddir/build/BUILD/gcc-4.8.5-20150702/obj-x86_64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.5-20150702/obj-x86_64-redhat-linux/cloog-install --enable-gnu-indirect-function --with-tune=generic --with-arch_32=x86-64 --build=x86_64-redhat-linux
Thread model: posix
gcc version 4.8.5 20150623 (Red Hat 4.8.5-11) (GCC)

# g++ test.cpp
In file included from test.cpp:2:0:
/usr/include/c++/4.8.2/valarray: In instantiation of 'class std::valarray<Logger>':
test.cpp:14:21: required from here
/usr/include/c++/4.8.2/valarray:926:5: error: cannot allocate an object of abstract type 'Logger'
     valarray<_Tp>::sum() const
     ^
test.cpp:4:7: note: because the following virtual functions are pure within 'Logger':
 class Logger {
       ^
test.cpp:9:18: note: virtual void Logger::write()
     virtual void write() = 0;
                  ^