I've just had a build fail on me with the following:

CC=/var/scratch/build/tools/bin/i386--netbsdelf-gcc 
/var/scratch/build/tools/bin/i386--netbsdelf-lint -chapbxzF -w -X 272 -d 
/var/scratch/build/dest/usr/include -D_LIBC -DLIBC_SCCS -DSYSLIBC_SCCS 
-D_REENTRANT -I/usr/src/lib/libc/include -DHESIOD -DINET6 -DNLS -DYP 
-D__DBINTERFACE_PRIVATE -I/usr/src/libexec/ld.elf_so 
-I/usr/src/lib/libc/dlfcn -DI18NMODULE_MAJOR=4 -DWITH_RUNE 
-I/usr/src/lib/libc -DRESOLVSORT -I. -DPOSIX_MISTAKE -DPORTMAP 
-DFLOATING_POINT -i LintSysNoerr.c
/var/scratch/build/dest/usr/include/ufs/lfs/lfs.h(529): incomplete 
structure or union pool: lfs_clpool [31]
/var/scratch/build/dest/usr/include/ufs/lfs/lfs.h(530): incomplete 
structure or union pool: lfs_bpppool [31]
/var/scratch/build/dest/usr/include/ufs/lfs/lfs.h(531): incomplete 
structure or union pool: lfs_segpool [31]
*** Error code 1

Stop.
nbmake: stopped in /usr/src/lib/libc

It's an unprived build, the only thing notable is that there is no
-I/var/scratch/build/dest/usr/include/sys in the above which contains
pool.h and thus the definition of struct pool.

Note: building with build.sh -U -T -M -D -R

Suggestions?