Parsers in modern compilers

Modern compilers and interpreters are based on different approaches to implement parsers. 

Brief overview of current state

• GCC 4.8.1 - hand-written top-down recursive descent parser
• Clang 3.3 - hand-written top-down recursive descent parser
• PathScale EkoPath 4 - hand-written top-down recursive descent parser (based on GCC frontend)
• Open64 5.0 - hand-written top-down recursive descent parser (based on GCC frontend)
• Cray Chapel 1.7.0 - bottom-up LALR(1) parser (generated by Bison), left-recursive grammar
• IBM X10 2.3.1 - bottom-up LALR(1) parser (generated by LPG)
• Ruby 2.0.0 - bottom-up LALR(1) parser (generated by Bison), left-recursive grammar
• PHP 5.5.0 - bottom-up LALR(1) parser (generated by Bison)
• Open JDK 7 - default: hand-written LALR parser; subproject: ANTLR based LL(*) parser
• Python 2.7.5 & 3.3.2 - hand-written top-down recursive descent parser
• Groovy 2.1.6 - LL(*) parser (generated by ANTLR)
• Go 1.1.1 - bottom-up LALR(1) parser (generated by Bison)
• Google V8 JavaScript Engine - hand-written top-down recursive descent parser
• Apple JavaScriptCore - hand-written top-down recursive descent parser