- Change the C++ directory entries to honor --sysroot if it is set.
- Don't define CROSS_INCLUDE_DIR for the cross compiler. Instead, set
TARGET_SYSTEM_ROOT to point to WORLDTMP and always define
STANDARD_INCLUDE_DIR.
- Change STANDARD_INCLUDE_DIR and the C++ include directories to just
start with "/usr" always. The compiler will prepend the sysroot when
doing cross-builds. GCC_INCLUDE_DIR (which contains headers that ship
with the compiler such as intrinsincs rather than OS-supplied headers)
remains hardcoded to look in TOOLS_PREFIX.
Reviewed by: bdrewery (older version)
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D15127
18ddcb43eb