Build failure cris-elf, gcc-5 backport of PR rtl-optimization/78255 fix, gcc/postreload.c:reload_cse_simplify

[Hans-Peter Nilsson <hans-peter dot nilsson at axis dot com>]

For cris-elf on the gcc-5-branch at r244321:

g++ -c   -g -O2 -DIN_GCC  -DCROSS_DIRECTORY_STRUCTURE  -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings   -DHAVE_CONFIG_H -I. -I. -I/tmp/hpautotest-gcc5/gcc/gcc -I/tmp/hpautotest-gcc5/gcc/gcc/. -I/tmp/hpautotest-gcc5/gcc/gcc/../include -I/tmp/hpautotest-gcc5/gcc/gcc/../libcpp/include -I/tmp/hpautotest-gcc5/cris-elf/gccobj/./gmp -I/tmp/hpautotest-gcc5/gcc/gmp -I/tmp/hpautotest-gcc5/cris-elf/gccobj/./mpfr -I/tmp/hpautotest-gcc5/gcc/mpfr -I/tmp/hpautotest-gcc5/gcc/mpc/src  -I/tmp/hpautotest-gcc5/gcc/gcc/../libdecnumber -I/tmp/hpautotest-gcc5/gcc/gcc/../libdecnumber/dpd -I../libdecnumber -I/tmp/hpautotest-gcc5/gcc/gcc/../libbacktrace   -o postreload.o -MT postreload.o -MMD -MP -MF ./.deps/postreload.TPo /tmp/hpautotest-gcc5/gcc/gcc/postreload.c
/tmp/hpautotest-gcc5/gcc/gcc/postreload.c: In function 'bool reload_cse_simplify(rtx_insn*, rtx)':
/tmp/hpautotest-gcc5/gcc/gcc/postreload.c:125:7: error: 'NO_FUNCTION_CSE' was not declared in this scope
make[2]: *** [postreload.o] Error 1

This seems to be due to your backport:

2017-01-11  Andre Vieira <andre.simoesdiasvieira@arm.com>

	Backport from mainline
	2016-12-09  Andre Vieira <andre.simoesdiasvieira@arm.com>

	PR rtl-optimization/78255
	* gcc/postreload.c (reload_cse_simplify): Do not CSE a function if
	NO_FUNCTION_CSE is true.

brgds, H-P