Proposed resolution:

Change 26.3.11 [cmplxh]:

The header behaves as if it includes the header <ccomplex>., and provides sufficient using declarations to declare in the global namespace all function and type names declared or defined in the neader <complex>. [Note: <complex.h> does not promote any interface into the global namespace as there is no C interface to promote. --end note]

Previously xxx.h was parsable by C++. But in the case of C99's <complex.h> it isn't. Otherwise we could model it just like <string.h>, <cstring>, <string>:

• <string> : C++ API in namespace std
• <cstring> : C API in namespace std
• <string.h> : C API in global namespace

In the case of C's complex, the C API won't compile in C++. So we have:

• <complex> : C++ API in namespace std
• <ccomplex> : ?
• <complex.h> : ?

The ? can't refer to the C API. TR1 currently says:

• <complex> : C++ API in namespace std
• <ccomplex> : C++ API in namespace std
• <complex.h> : C++ API in global namespace