byte-optimize-logbyte-optimize-log is a variable defined in `
bytecomp.el'. Its value is
nilDocumentation: If non-nil, the byte-compiler will log its optimizations. If this is 'source, then only source-level optimizations will be logged. If it is 'byte, then only byte-level optimizations will be logged. The information is logged to `byte-compile-log-buffer'. You can customize this variable.