Question

I have the following very simple application that compiles and runs fine:

EDIT: changed the example to be simpilar to end confusion of the real issue

int main() {
    return 0;
}

As soon as I add #include <string> (and not even reference std::string), it fails to compile and I get the following error:

/usr/include/c++/4.1.2/bits/allocator.h:82 error: expected template-name before '<' token

Along with about 456 other, similar errors.

Any ideas? Thanks!

UPDATE:

Line 82 of /usr/include/c++/4.1.2/bits/allocator.h references the template __glibcxx_base_allocator at the location of the error. That template is defined in bits/c++allocator.h. When I search the system for that file, I get 3 hits, but none of them are in /usr/include/c++/4.1.2/bits/ as one would expect.

I have version 3.1.6, 4.1.1, and 4.3.2, but not 4.1.2 as the rest of the includes I am using. I am not sure which one is being used (if any, however, I don’t get any error for an unknown file), but it seems the problem may stem from this.

Answer 1

The problem appears to be the installed development packages are not correct or incomplete (not to be confused with corrupt). Forcing g++ to use different include versions corrects that:

g++ -nostdic++ hello.cc -o hello -I/usr/include/c++/3.4.6

All the alternative directories (4.1.1, 4.1.2 and 4.3.2) are incomplete causing inappropriate files to be included causing the unusually errors. For example:

/usr/include/c++/4.1.2/bits/allocator.h requires __glibcxx_base_allocator located in bits/c++allocator.h which is being included from either /usr/include/c++/4.1.1 or /usr/include/c++/4.3.2 and appear to be incompatible. Forcing the compiler to use the only complete set of includes rectifies this.