What compiler technology is used to build the compilers?
Gccgo has a C++ front-end with a recursive descent parser coupled to the standard GCC back end. Gc is written in C using yacc/bison for the parser. Although it’s a new program, it fits in the Plan 9 C compiler suite (http://plan9.bell-labs.com/sys/doc/compiler.html) and uses a variant of the Plan 9 loader to generate ELF binaries. We considered writing 6g, the original Go compiler, in Go itself but elected not to do so because of the difficulties of bootstrapping and especially of open source distribution—you’d need a Go compiler to set up a Go environment. Gccgo, which came later, makes it possible to consider writing a compiler in Go, which might well happen. (Go would be a fine language in which to implement a compiler; a native lexer and parser are already available in /pkg/go.) We also considered using LLVM for 6g but we felt it was too large and slow to meet our performance goals.
