pr_debug() and #define DEBUG usage

[Randy.Dunlap]

Hi,

Some drivers, filesystems, subsystems, and libraries #define or use
DEBUG locally in their source files.  This can conflict with DEBUG
in include/linux/kernel.h, specifically the "pr_debug" macro, which
has over 300 uses (invocations, calls) in 2.5.52 spread throughout
drivers, libraries, and filesystems.

Question:
How should DEBUG be enabled for use by include/linux/kernel.h ?
a.  change CFLAGS_KERNEL in linux/Makefile to include "-DDEBUG"
b.  #define DEBUG in include/linux/kernel.h
c.  #define DEBUG in each file where someone wants to enable it
d.  others?

"DEBUG" seems heavily used (or overused, misused, abused) and too
generic.

And in one place, it keeps a kernel build from completing when
DEBUG is defined.  In lib/inflate.c, line 999:
  fprintf(stderr, "<%u> ", h);
gcc just doesn't like this line.

-- 
~Randy