You can't use a typedef from a typename scope in a template This is obviously a major bug and it means you can't access the typedefs of the ISO standard library containers in order to use safe types to manipulate those containers, when typename is such a container.
Here is the output of the command g++ bug_report_typedef.cc bug_report_typedef.cc: In function âvoid f(T)â: bug_report_typedef.cc:3: error: expected â;â before âiâ g++ -v follows the source code of bug_report_typedef.cc template <typename T> void f(T t){ T::type i; } g++ -v bug_report_typedef.cc Using built-in specs. Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Debian 4.4.4-3' --with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --enable-shared --enable-multiarch --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.4 --program-suffix=-4.4 --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc --with-arch-32=i486 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.4.4 (Debian 4.4.4-3) COLLECT_GCC_OPTIONS='-v' '-shared-libgcc' '-mtune=generic' /usr/lib/gcc/x86_64-linux-gnu/4.4.4/cc1plus -quiet -v -D_GNU_SOURCE bug_report_typedef.cc -quiet -dumpbase bug_report_typedef.cc -mtune=generic -auxbase bug_report_typedef -version -o /tmp/ccgt4Dk8.s GNU C++ (Debian 4.4.4-3) version 4.4.4 (x86_64-linux-gnu) compiled by GNU C version 4.4.4, GMP version 4.3.2, MPFR version 2.4.2-p1. GGC heuristics: --param ggc-min-expand=57 --param ggc-min-heapsize=51739 ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu" ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/4.4.4/../../../../x86_64-linux-gnu/include" ignoring nonexistent directory "/usr/include/x86_64-linux-gnu" #include "..." search starts here: #include <...> search starts here: /usr/include/c++/4.4 /usr/include/c++/4.4/x86_64-linux-gnu /usr/include/c++/4.4/backward /usr/local/include /usr/lib/gcc/x86_64-linux-gnu/4.4.4/include /usr/lib/gcc/x86_64-linux-gnu/4.4.4/include-fixed /usr/include End of search list. GNU C++ (Debian 4.4.4-3) version 4.4.4 (x86_64-linux-gnu) compiled by GNU C version 4.4.4, GMP version 4.3.2, MPFR version 2.4.2-p1. GGC heuristics: --param ggc-min-expand=57 --param ggc-min-heapsize=51739 Compiler executable checksum: a92c574e76687c18572fdbea97434cec bug_report_typedef.cc: In function âvoid f(T)â: bug_report_typedef.cc:3: error: expected â;â before âiâ -- Summary: you can't use a typedef from a typename scope in a template Product: gcc Version: 4.4.4 Status: UNCONFIRMED Severity: major Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: gcc at razorcam dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44559