1# The -mdynamic-no-pic ensures that the compiler executable is built without 2# position-independent-code -- the usual default on Darwin. This speeds compiles 3# by 8-20% (measurements made against GCC-11). 4# However, we cannot add it unless the bootstrap compiler supports 5# -mno-dynamic-no-pic to undo it, since libiberty, at least, needs this. 6 7#��We use Werror, since some versions of clang report unknown command line flags 8# as a warning only. 9 10# We only need to determine this for the host tool used to build stage1 (or a 11# non-bootstrapped compiler), later stages will be built by GCC which supports 12# the required flags. 13 14# We cannot use mdynamic-no-pic when building shared host resources. 15 16ifeq (${host_shared},no) 17BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC := $(shell \ 18 $(CC) -S -xc /dev/null -o /dev/null -Werror -mno-dynamic-no-pic 2>/dev/null \ 19 && echo true) 20else 21BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC := false 22endif 23 24@if gcc-bootstrap 25ifeq (${BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC},true) 26STAGE1_CFLAGS += -mdynamic-no-pic 27else 28STAGE1_CFLAGS += -fPIC 29endif 30ifeq (${host_shared},no) 31# Add -mdynamic-no-pic to later stages when we know it is built with GCC. 32BOOT_CFLAGS += -mdynamic-no-pic 33endif 34@endif gcc-bootstrap 35 36@unless gcc-bootstrap 37ifeq (${BOOTSTRAP_TOOL_CAN_USE_MDYNAMIC_NO_PIC},true) 38# FIXME: we should also enable this for cross and non-bootstrap builds but 39# that needs amendment to libcc1. 40# CFLAGS += -mdynamic-no-pic 41# CXXFLAGS += -mdynamic-no-pic 42else 43CFLAGS += -fPIC 44CXXFLAGS += -fPIC 45endif 46@endunless gcc-bootstrap 47