https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85669
--- Comment #19 from Douglas Mencken <dougmencken at gmail dot com> --- I dunno are such warnings related or not echo timestamp > s-gtype ccache /Developer/GCC/7.3p/PowerPC/32bit/bin/g++ -std=gnu++98 -fno-PIE -c -g -mdynamic-no-pic -DIN_GCC -fno-exceptions -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual -Wno-format -Wmissing-format-attribute -Woverloaded-virtual -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -DHAVE_CONFIG_H -I. -I. -I../../gcc-8.2.0/gcc -I../../gcc-8.2.0/gcc/. -I../../gcc-8.2.0/gcc/../include -I../../gcc-8.2.0/gcc/../libcpp/include -I/Volumes/LibreOffice/TheGCC/_build_8.2/./gmp -I/Volumes/LibreOffice/TheGCC/gcc-8.2.0/gmp -I/Volumes/LibreOffice/TheGCC/_build_8.2/./mpfr/src -I/Volumes/LibreOffice/TheGCC/gcc-8.2.0/mpfr/src -I/Volumes/LibreOffice/TheGCC/gcc-8.2.0/mpc/src -I../../gcc-8.2.0/gcc/../libdecnumber -I../../gcc-8.2.0/gcc/../libdecnumber/dpd -I../libdecnumber -I../../gcc-8.2.0/gcc/../libbacktrace -I/Volumes/LibreOffice/TheGCC/_build_8.2/./isl/include -I/Volumes/LibreOffice/TheGCC/gcc-8.2.0/isl/include -o explow.o -MT explow.o -MMD -MP -MF ./.deps/explow.TPo ../../gcc-8.2.0/gcc/explow.c ../../gcc-8.2.0/gcc/explow.c: In function 'rtx_def* round_push(rtx)': ../../gcc-8.2.0/gcc/explow.c:989:248: warning: self-comparison always evaluates to false [-Wtautological-compare] if (!SUPPORTS_STACK_ALIGNMENT ~~~~~~~~~~~~~~~~~~~~~~~ ^ ../../gcc-8.2.0/gcc/explow.c: In function 'void emit_stack_restore(save_level, rtx)': ../../gcc-8.2.0/gcc/explow.c:1104:247: warning: self-comparison always evaluates to false [-Wtautological-compare] if (SUPPORTS_STACK_ALIGNMENT) ~~~~~~~~~~~~~~~~~~~~~~~~ ^ rm -rf libbackend.a