Embedded toolchains face conflicting requirements from different customers. Some need the best possible speed while others are tightly size constrained. To avoid having every toolchain user need to re-compile all libraries, it's convenient to add -Os/-Oz as an additional multilib selector so that provided libraries will be built both ways.
This series provides a new configure time options, --enable-multilib-space, which takes each library configuration and adds a duplicate with -Os appended. When this option is not enabled, there is no effect on the resulting toolchain. This series includes a couple of preparatory changes: * To make this pass the right compiler flags while building libgcc, any -Os or -Oz option included in CFLAGS is appended to the arguments to override the -O2 option present in LIBGCC2_CFLAGS. * The arm multilib configuration was missing a couple of MULTILIB_DEFAULTS values that don't affect "normal" operation but break things when -Os is added. Keith Packard (3): libgcc: Use -Os/-Oz from CC or CFLAGS arm: Add missing multilib default values gcc: Add --enable-multilib-space option config-ml.in | 2 +- gcc/Makefile.in | 32 +++++++++++++++++++++++++++----- gcc/config/arm/arm-mlib.h | 2 +- gcc/configure | 13 +++++++++++++ gcc/configure.ac | 7 +++++++ gcc/doc/install.texi | 12 ++++++++++++ libgcc/Makefile.in | 10 +++++++--- 7 files changed, 68 insertions(+), 10 deletions(-) -- 2.49.0
