configure with --enable-malloc-debugging fails to compile

[Jim Kleckner <jek-cygwin2 at kleckner dot net>]

FYI, the --enable-malloc-debugging option fails to compile with current
CVS sources.

(/oss/src/configure --prefix=/oss/mdebug.install --enable-debugging 
--enable-malloc-debugging -v; make) >& make.out

I'm attaching the tail end of the make output.
g++ -L/oss/mdebug.build/i686-pc-cygwin/winsup -L/oss/mdebug.build/i686-pc-cygwin/winsup/cygwin -L/oss/mdebug.build/i686-pc-cygwin/winsup/w32api/lib -isystem /oss/src/winsup/include -isystem /oss/src/winsup/cygwin/include -isystem /oss/src/winsup/w32api/include -B/oss/mdebug.build/i686-pc-cygwin/newlib/ -isystem /oss/mdebug.build/i686-pc-cygwin/newlib/targ-include -isystem /oss/src/newlib/libc/include -c -nostdinc++  -DHAVE_CONFIG_H  -O2 -g -g -O2   -MMD -fomit-frame-pointer -fmerge-constants -ftracer  -Wall -Wstrict-aliasing -Wwrite-strings -fno-common -pipe -fbuiltin -fmessage-length=0  -I.  -I/oss/src/winsup/cygwin  -I/oss/src/winsup/w32api/include -I/oss/src/winsup/cygwin/config/i386 -I/usr/lib/gcc/i686-pc-cygwin/3.4.4/include -fno-rtti -fno-exceptions -o ./flock.o /oss/src/winsup/cygwin/flock.cc
gcc -L/oss/mdebug.build/i686-pc-cygwin/winsup -L/oss/mdebug.build/i686-pc-cygwin/winsup/cygwin -L/oss/mdebug.build/i686-pc-cygwin/winsup/w32api/lib -isystem /oss/src/winsup/include -isystem /oss/src/winsup/cygwin/include -isystem /oss/src/winsup/w32api/include -B/oss/mdebug.build/i686-pc-cygwin/newlib/ -isystem /oss/mdebug.build/i686-pc-cygwin/newlib/targ-include -isystem /oss/src/newlib/libc/include -c  -DHAVE_CONFIG_H  -O2 -g -g -O2   -MMD  -fmerge-constants -ftracer  -Wall -Wstrict-aliasing -Wwrite-strings -fno-common -pipe -fbuiltin -fmessage-length=0  -I.  -I/oss/src/winsup/cygwin  -I/oss/src/winsup/w32api/include -I/oss/src/winsup/cygwin/config/i386 -I/usr/lib/gcc/i686-pc-cygwin/3.4.4/include -o ./fnmatch.o /oss/src/winsup/cygwin/libc/fnmatch.c
g++ -L/oss/mdebug.build/i686-pc-cygwin/winsup -L/oss/mdebug.build/i686-pc-cygwin/winsup/cygwin -L/oss/mdebug.build/i686-pc-cygwin/winsup/w32api/lib -isystem /oss/src/winsup/include -isystem /oss/src/winsup/cygwin/include -isystem /oss/src/winsup/w32api/include -B/oss/mdebug.build/i686-pc-cygwin/newlib/ -isystem /oss/mdebug.build/i686-pc-cygwin/newlib/targ-include -isystem /oss/src/newlib/libc/include -c -nostdinc++  -DHAVE_CONFIG_H  -O2 -g -g -O2   -MMD  -fmerge-constants -ftracer  -Wall -Wstrict-aliasing -Wwrite-strings -fno-common -pipe -fbuiltin -fmessage-length=0  -I.  -I/oss/src/winsup/cygwin  -I/oss/src/winsup/w32api/include -I/oss/src/winsup/cygwin/config/i386 -I/usr/lib/gcc/i686-pc-cygwin/3.4.4/include -fno-rtti -fno-exceptions -o ./fork.o /oss/src/winsup/cygwin/fork.cc
In file included from /oss/src/winsup/cygwin/fork.cc:31:
/oss/src/winsup/cygwin/cygmalloc.h:14: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:14: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:14: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:14: error: declaration of C function `void free_dbg(void*, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:62: error: previous declaration `void free_dbg(void*, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:15: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:15: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:15: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:15: error: declaration of C function `void* malloc_dbg(unsigned int, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:61: error: previous declaration `void* malloc_dbg(size_t, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:16: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:16: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:16: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:16: error: declaration of C function `void* realloc_dbg(void*, unsigned int, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:63: error: previous declaration `void* realloc_dbg(void*, size_t, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:17: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:17: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:17: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:17: error: declaration of C function `void* calloc_dbg(size_t, size_t, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:64: error: previous declaration `void* calloc_dbg(size_t, size_t, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:18: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:18: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:18: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:18: error: declaration of C function `void* memalign_dbg(size_t, size_t, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:65: error: previous declaration `void* memalign_dbg(size_t, size_t, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:19: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:19: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:19: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:19: error: declaration of C function `void* valloc_dbg(size_t, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:66: error: previous declaration `void* valloc_dbg(size_t, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:20: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:20: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:20: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:20: error: declaration of C function `size_t malloc_usable_size_dbg(void*, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:69: error: previous declaration `size_t malloc_usable_size_dbg(void*, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:21: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:21: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:21: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:21: error: declaration of C function `int malloc_trim_dbg(size_t, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:68: error: previous declaration `int malloc_trim_dbg(size_t, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:22: error: expected identifier before string constant
/oss/src/winsup/cygwin/cygmalloc.h:22: error: expected `,' or `...' before string constant
/oss/src/winsup/cygwin/cygmalloc.h:22: error: ISO C++ forbids declaration of `parameter' with no type
/oss/src/winsup/cygwin/cygmalloc.h:22: error: declaration of C function `int mallopt_dbg(int, int, int)' conflicts with
/oss/src/winsup/cygwin/dlmalloc.h:71: error: previous declaration `int mallopt_dbg(int, int, const char*, int)' here
/oss/src/winsup/cygwin/cygmalloc.h:23: error: variable or field `malloc_stats_dbg' declared void
/oss/src/winsup/cygwin/cygmalloc.h:23: error: `int malloc_stats_dbg' redeclared as different kind of symbol
/oss/src/winsup/cygwin/dlmalloc.h:70: error: previous declaration of `void malloc_stats_dbg(const char*, int)'
/oss/src/winsup/cygwin/cygmalloc.h:23: error: declaration of `int malloc_stats_dbg'
/oss/src/winsup/cygwin/dlmalloc.h:70: error: conflicts with previous declaration `void malloc_stats_dbg(const char*, int)'
/oss/src/winsup/cygwin/cygmalloc.h:23: error: initializer expression list treated as compound expression
/oss/src/winsup/cygwin/cygmalloc.h:23: warning: left-hand operand of comma has no effect
make[3]: *** [fork.o] Error 1
make[3]: Leaving directory `/oss/mdebug.build/i686-pc-cygwin/winsup/cygwin'
make[2]: *** [cygwin] Error 1
make[2]: Leaving directory `/oss/mdebug.build/i686-pc-cygwin/winsup'
make[1]: *** [all-target-winsup] Error 2
make[1]: Leaving directory `/oss/mdebug.build'
make: *** [all] Error 2