Specifies a debug section.
.debug
This directive is appropriate if you must provide certain debugging information explicitly, in a debug section. But this directive turns off automatic generation of debugging information (which the assembler does if you enable the debugger). Furthermore, this directive tells the assembler to ignore the debugging directives .file, .function, .line, .size, and .type.
As Debugging Directives explains, using the .debug directive may be the least common method of providing debugging information to the assembler.