Quoting From Vulcan Overview
Vulcan had four primary goals.
• Portability: Vulcan was developed simultaneously on four platforms: 32 bit
Windows using the Microsoft compiler from Visual Studio 7, 32 bit Linux and 64
bit Linux for AMD64/Opteron using various versions of gcc, and 64 bit Solaris
using the Sun Forte C++ compiler. Ports exist to 64-bit MVS UNIX, Itanium, and
AIX. See the Portability section.
Firebird V1.5 and V2.0 are sensitive to minor variations in C++ compilers, which is a
serious liability given the somewhat cavalier attitude of compiler developers toward
Vulcan was developed on four compilers simultaneously: gcc 2.96, gcc 3.3.4,
Solaris/Forte 5.5, and Microsoft VC7. To make that work, Vulcan eliminated the
dependency on std.lib, minimized all other dependencies outside the core clib (c library),
and reduced the complexity of template usage