# # OS/161 build environment base definitions # # Proper usage: # TOP=../.. # or however many levels needed # .include "$(TOP)/mk/os161.config.mk" # # This file takes care of including $(TOP)/defs.mk and sets defaults # for things that can be defined there. # # It and defs.mk collaboratively set various make variables that # control the build environment. # ############################################################ # # These build variables are meant to be user-settable: # # (Locations.) # # OSTREE The root directory you run OS/161 in. # Default is ~/os161/root. # # WORKDIR Top of a tree to use for compiling. # Default is $(TOP)/build. # # BUILDSYMLINKS If set to "yes", symlinks in each directory # will be made to point into $(BUILDTOP). # Default is "yes". # # By default the system will be built within the source tree and # installed to ~/os161/root. It is expected this will be sufficient # for most uses. If your root directory is somewhere else, set OSTREE # in defs.mk. If you're running on a large computing cluster with # networked home directories, setting WORKDIR to point somewhere on a # local disk will probably make your builds quite a bit faster, at the # cost of having to recompile if you switch to a different machine. # If you want the source tree to be completely read-only, which is # occasionally useful for tracking down build glitches, you can set # WORKDIR and also set BUILDSYMLINKS to no. # # (Platform.) # # PLATFORM The type of system we're building for. # Should always be set by defs.mk. # # MACHINE The processor type we're building for. # Should always be set by defs.mk. # # The target machine type is set when you configure the source tree. # If you change it, be sure to make distclean and recompile everything. # Not all possible combinations of PLATFORM and MACHINE are allowed. # See the logic at the bottom of this file for a list of supported # combinations. If you are trying to port OS/161 to a new machine, the # first step is to update that list. # # (Compilation.) # # DEBUG Compiler option for debug vs. optimize. # Default: -O2 # # WARNINGS Compiler options for warnings. # Default: -Wall -Wextra -Wwrite-strings # -Wmissing-prototypes # # WERROR Compiler option to make warnings fatal. # Default: -Werror # # Since debugging of user-level programs is not supported in OS/161 # (and not really supportable without a lot of work on your part) # there's usually not much reason to change DEBUG. If you want to, # however, the easiest way is to usually set it on the make command # line: # make clean # make DEBUG=-g all # recompiles the current directory with debug info. # # Similarly, if you have a lot of warnings and you want to temporarily # ignore them while you fix more serious problems, you can turn off # the error-on-warning behavior on the fly by setting WERROR to empty: # make WERROR= # # This convenience is why these variables are separately defined # rather than just being rolled into CFLAGS. # ############################################################ # # These build variables can be set explicitly for further control if # desired, but should in general not need attention. # # (Locations.) # # BUILDTOP Top of tree where .o files go. # Default is $(WORKDIR). # # TOOLDIR Place for compiled programs used in # the build. Default is $(WORKDIR)/tooldir. # # INSTALLTOP Staging directory for installation. # Default is $(WORKDIR)/install # # Probably the only reason to change these would be if you're short on # diskspace in $(WORKDIR). # # (Platform.) # # GNUTARGET The GNU gcc/binutils name for the # target we're building for. # Defaults to $(MACHINE)-harvard-os161. # # This should not need to be changed. # # (Programs.) # # CC (Cross-)compiler. # Default is $(GNUTARGET)-gcc. # # LDCC (Cross-)compiler when invoked for linking. # Default is $(CC). # # AS (Cross-)assembler. # Default is $(GNUTARGET)-as. # # LD (Cross-)linker. # Default is $(GNUTARGET)-ld. # # AR Archiver (librarian). # Default is $(GNUTARGET)-ar. # # RANLIB Library postprocessor/indexer. # Default is $(GNUTARGET)-ranlib. # # NM Tool to print symbol tables. # Default is $(GNUTARGET)-nm. # # SIZE Tool to print sizes of binaries. # Default is $(GNUTARGET)-size. # # STRIP Tool to remove debugging information. # Default is $(GNUTARGET)-strip. # # The above are the compilation tools for OS/161. They create programs # that run on OS/161. Since OS/161 is not meant to be self-hosting, # programs that we need to run during the build, or run manually # outside of the machine simulator, need to be compiled with a # different compiler that creates programs that run for the "host" OS, # whatever that is (Linux, NetBSD, FreeBSD, MacOS X, Solaris, etc.) # The host compilation tools are prefixed with HOST_ as follows: # # # HOST_CC Host compiler. # Default is gcc. # # HOST_LDCC Host compiler when invoked for linking. # Default is $(HOST_CC). # # HOST_AS Host assembler. # Default is as. # # HOST_LD Host linker. # Default is ld. # # HOST_AR Host archiver (librarian). # Default is ar. # # HOST_RANLIB Host library postprocessor/indexer. # Default is ranlib. # # HOST_NM Host tool to print symbol tables. # Default is nm. # # HOST_SIZE Host tool to print sizes of binaries. # Default is size. # # HOST_STRIP Host tool to remove debugging information. # Default is strip. # # In general there should be no need to change the cross-compiler # variables, unless you are e.g. trying to build OS/161 with something # other than gcc, or you want to supply an explicit location for a # specific copy of gcc somewhere rather than use the one on your # $PATH. # # However, on some systems it might conceivably be necessary to change # the host tool variables. For example, there are some (now extremely # old) systems where "ranlib" is not only not needed but also corrupts # libraries, in which case you might set HOST_RANLIB=true. If your # host machine doesn't have "gcc" you may be able to set HOST_CC=cc # and fiddle with HOST_WARNINGS and HOST_CFLAGS (below) and have # things still more or less work. # # (Compilation.) # # HOST_DEBUG Like DEBUG, but for programs to be # built to run on the host OS. # Default is $(DEBUG). # # HOST_WARNINGS Like WARNINGS, but for programs to be # built to run on the host OS. # Default is $(WARNINGS). # # HOST_WERROR Like WERROR, but for programs to be # built to run on the host OS. # Default is $(WERROR). # ############################################################ # # These build variables should probably not be tinkered with in # defs.mk and serve as baseline values to be added to by individual # program makefiles and used by other os161.*.mk files. # # (Compilation.) # # CFLAGS Full baseline compile flags. # Default is $(DEBUG) $(WARNINGS) $(WERROR), # plus what's needed for -nostdinc. # # KCFLAGS Like CFLAGS, but for the kernel, which # configures debug/optimize separately. # Default is $(KDEBUG) $(WARNINGS) $(WERROR). # (KDEBUG is set by the kernel config script.) # # HOST_CFLAGS Like CFLAGS, but for programs to be # built to run on the host OS. Default is # $(HOST_DEBUG) $(HOST_WARNINGS) $(HOST_WERROR). # # LDFLAGS Baseline link-time flags. # Default is empty plus what's needed for # -nostdlib. # # KLDFLAGS Baseline link-time flags for kernel. # Default is empty. # # HOST_LDFLAGS Like LDFLAGS, but for programs to be # built to run on the host OS. # Default is empty. # # LIBS Baseline list of libraries to link to. # Default is empty plus what's needed for # -nostdlib. # # HOST_LIBS Like LIBS, but for programs to be # built to run on the host OS. # Default is empty. # ############################################################ # # These variables should not be changed directly, or by individual # program makefiles either, and are for use by other os161.*.mk files. # # (Locations.) # # MYDIR Name of current source directory, relative # to $(TOP); e.g. bin/sh. # # MYBUILDDIR Build directory for current source directory. # # MKDIRS Directories to create, mostly for installing. # # ABSTOP_PATTERN, ABSTOP Private, used to compute other locations. # # (Compilation.) # # MORECFLAGS Same as CFLAGS but comes later on the # compile command line. In general individual # makefiles shouldn't touch this. # Default is empty plus what's needed for # -nostdinc. # # MORELIBS Same as LIBS but comes after on the link # line. In general individual makefiles # shouldn't touch this. # Default is empty plus what's needed for # -nostdlib. # ############################################################ # Some further vars that currently exist but should be moved # around elsewhere: # # COMPAT_CFLAGS # COMPAT_TARGETS ############################################################ # Establish defaults. # (Variables are set in the order documented above.) # # These definitions are set firmly here (that is, not with ?=) because # some of them, like CC, are predefined by make. Because defs.mk is # included afterwards it can override any of these settings. # # # User-settable configuration # # Locations of things. OSTREE=$(HOME)/os161/root # Root directory to install into. WORKDIR=$(TOP)/build # Top of tree to build into. BUILDSYMLINKS=yes # yes => link build -> $(BUILDTOP)/$(HERE). # Platform we're building for. PLATFORM=sys161 MACHINE=mips # Compilation DEBUG=-O2 WARNINGS=-Wall -W -Wwrite-strings -Wmissing-prototypes WERROR=-Werror # # Less-likely-to-need-setting # # Locations of things. BUILDTOP=$(WORKDIR) # Top of directory for compiler output. TOOLDIR=$(WORKDIR)/tooldir # Place for host progs used in the build. INSTALLTOP=$(WORKDIR)/install # Staging area for installation. # Platform. GNUTARGET=$(MACHINE)-harvard-os161 # Programs and tools. CC=$(GNUTARGET)-gcc # Compiler. LDCC=$(CC) # Compiler when used for linking. AS=$(GNUTARGET)-as # Assembler. LD=$(GNUTARGET)-ld # Linker. AR=$(GNUTARGET)-ar # Archiver. RANLIB=$(GNUTARGET)-ranlib # Library indexer. NM=$(GNUTARGET)-nm # Symbol dumper. SIZE=$(GNUTARGET)-size # Size tool. STRIP=$(GNUTARGET)-strip # Debug strip tool. HOST_CC=gcc # Host compiler. HOST_LDCC=$(HOST_CC) # Host compiler when used for linking. HOST_AS=as # Host assembler. HOST_LD=ld # Host linker. HOST_AR=ar # Host archiver. HOST_RANLIB=ranlib # Host library indexer. HOST_NM=nm # Host symbol dumper. HOST_SIZE=size # Host size tool. HOST_STRIP=strip # Host debug strip tool. # Compilation. HOST_DEBUG=$(DEBUG) HOST_WARNINGS=$(WARNINGS) HOST_WERROR=$(WERROR) # # Probably-shouldn't-be-touched # CFLAGS=$(DEBUG) $(WARNINGS) $(WERROR) -std=gnu99 KCFLAGS=$(KDEBUG) $(WARNINGS) $(WERROR) -std=gnu99 HOST_CFLAGS=$(HOST_DEBUG) $(HOST_WARNINGS) $(HOST_WERROR) \ -I$(INSTALLTOP)/hostinclude LDFLAGS= KLDFLAGS= HOST_LDFLAGS= LIBS= HOST_LIBS= # # Don't touch. # MORECFLAGS= MORELIBS= # lib/hostcompat. COMPAT_CFLAGS= COMPAT_TARGETS= ############################################################ # Get defs.mk to get the real configuration for this tree. # If it doesn't exist, we'll go with the defaults. .-include "$(TOP)/defs.mk" # UW Mod # This needs to come after the above include. .if defined(TOOLPREFIX) CC=$(TOOLPREFIX)gcc # Compiler. LDCC=$(CC) # Compiler when used for linking. AS=$(TOOLPREFIX)as # Assembler. LD=$(TOOLPREFIX)ld # Linker. AR=$(TOOLPREFIX)ar # Archiver. RANLIB=$(TOOLPREFIX)ranlib # Library indexer. NM=$(TOOLPREFIX)nm # Symbol dumper. SIZE=$(TOOLPREFIX)size # Size tool. STRIP=$(TOOLPREFIX)strip # Debug strip tool. .endif ############################################################ # Make sure we have a supported PLATFORM and MACHINE. # We support mips on system/161. SUPPORTED_TARGETS=sys161 mips _OK_=0 .for _P_ _M_ in $(SUPPORTED_TARGETS) .if "$(PLATFORM)" == "$(_P_)" && "$(MACHINE)" == "$(_M_)" _OK_=1 .endif .endfor .if "$(_OK_)" != "1" .init: @echo "Platform $(PLATFORM) and machine $(MACHINE) not supported" @false .endif ############################################################ # Get any machine-dependent flags or makefile definitions .-include "$(TOP)/mk/os161.config-$(MACHINE).mk" ############################################################ # Establish some derived locations. # # Absolute location of the top of the source tree. This should only be # used to un-absolutize other paths; the tree ought to be independent # of where it happens to live. # # This works by turning $(TOP) into a regexp and substituting it into # the current directory. Note that it doesn't escape all regexp # metacharacters -- if you make a directory named "foo*bar" or # something you deserve the consequences. # # .CURDIR is a make builtin. # ABSTOP_PATTERN=$(TOP:S/./\\./g:S/\\.\\./[^\/]*/g) ABSTOP=$(.CURDIR:C/$(ABSTOP_PATTERN)\$//) # Find the name of the current directory relative to TOP. # This works by removing ABSTOP from the front of .CURDIR. MYDIR=$(.CURDIR:S/^$(ABSTOP)//) # Find the build directory corresponding to the current source dir. .if "$(MYDIR)" == "" # avoid stray slash MYBUILDDIR=$(BUILDTOP) .else MYBUILDDIR=$(BUILDTOP)/$(MYDIR) .endif ############################################################ # Ensure we compile a consistent tree. # # Traditionally in Unix the first step of recompiling the system is to # install new header files. Furthermore, the second step is to compile # and install new libraries, before continuing on to the rest of the # OS, which can then be compiled with those new headers and new # libraries. # # Combining the compile and install phases like this is simpler and # uses less disk space on extra copies of things (which mattered, back # in the day) but has a number of problems. Chief among these is that # if the build bombs out halfway through you end up with a partly # updated and maybe broken system. It also means that once you start # recompiling the system you can't easily back out. And the behavior # violates the principle of least surprise. # # OS/161 1.x had, intentionally, a very traditional build environment. # In OS/161 2.x, however, we use a staging area to avoid mixing build # and install. This means that we must compile only against the # staging area, $(INSTALLTOP), and never use the headers or libraries # installed in $(OSTREE) until install time. # # This means that regardless of whether we have a gcc configured so it # includes from our $(OSTREE) by default or not, we must use -nostdinc # and -nostdlib and explicitly link with materials from $(INSTALLTOP). # # Use MORECFLAGS and MORELIBS, which are supported by os161.compile.mk # for this purpose, so the include paths and library list come out in # the right order. # CFLAGS+=-nostdinc MORECFLAGS+=-I$(INSTALLTOP)/include LDFLAGS+=-nostdlib -L$(INSTALLTOP)/lib $(INSTALLTOP)/lib/crt0.o MORELIBS+=-lc LIBDEPS+=$(INSTALLTOP)/lib/crt0.o $(INSTALLTOP)/lib/libc.a ############################################################ # end.