[LLVMdev] Makefile.rules Changes / automake update (IMPORTANT!)

Fri Oct 22 15:14:33 PDT 2004

s/building libraries/building loadable modules/

Libaries work fine out of the box, it's modules you'd pass to e.g. opt
-load that don't.

On Fri, 22 Oct 2004 15:13:17 -0700, Michael McCracken
<michael.mccracken at gmail.com> wrote:
> Hi Reid, just a quick note while you're doing this, a while ago I ran
> into a problem that the standard makefiles weren't building libraries
> (like, say, a new pass) correctly on OS X - they were being built as
> shared libraries and not bundles, so they couldn't be loaded with
> dlopen. The discussion is in the archives if you want more details...
> 
> I fixed it locally by doing the following hack:
> 
> % diff Makefile.rules.old Makefile.rules
> 326c326
> < Link     := $(LIBTOOL) --mode=link $(CXX)
> ---
> > Link     := $(LIBTOOL) --mode=link $(CXX) -module
> 
> (Note that libtool on OS X is not quite gnu libtool)
> 
> If there's a saner way to incorporate this fix, now might be the time,
> since you're working on it already.
> 
> Hope this isn't piling too much work on, but it'd be nice to not have
> to worry about keeping this local change.
> 
> Thanks!
> -mike
> 
> 
> 
> 
> On Fri, 22 Oct 2004 14:40:42 -0700, Reid Spencer <reid at x10sys.com> wrote:
> > Hello,
> >
> > I've closed PR106 (use automake) as WONTFIX. I've already delineated the
> > problems with automake in previous posts but as of now, all the automake
> > related stuff has been removed from the repository.
> >
> > In an effort to start making our makefile system better, I've committed changes
> > to Makefile.rules and a few library Makefiles that nearly double the speed of
> > our compilations. I can now build all of LLVM (lib, utils, tools, runtime,
> > examples) in just over 17 minutes on my system. This used to take over 30
> > minutes. There are two main speed ups: (a) we do automatic dependency checking
> > in one pass instead of two, and (b) we use "ar" to archive libraries, not
> > libtool. The first change makes the build generally go faster in all
> > directories. The second change speeds up links slightly because libraries are
> > properly searched for symbols. I have also removed redundant variable
> > definitions and sub-shell invocations (replaced with GNU Make features).
> >
> > I have tested these changes quite extensively including the Stacker, sample,
> > llvm-test, Java and reopt projects. If you have another project, you MIGHT be
> > impacted because of a few variable name changes.
> >
> > All changes will (soon) be documented in a new "LLVM Makefiles" document that
> > I'll write, but quickly, here's what changed from a USER's perspective:
> >
> > * ExtraSource variable became BUILT_SOURCES (standard variable name)
> > * SourceDir variable eliminated (redundant with BUILD_SRC_DIR, few uses)
> > * Properly allow standard variables to be used (C,CFLAGS,CXX,CXXFLAGS,CPP,
> >    CPPFLAGS, LD, LDFLAGS, AR, ARFLAGS, etc) to alter compilation settings on a
> >    per directory basis.
> > * Build BUILT_SOURCES first (ensures *.td -> *.inc translation occurs)
> > * Dependency information is now, by default, generated on every compile. This
> >    keeps it constantly up to date. System headers are not tracked so as to
> >    reduce make's load time. There is no separate dependency generation pass.
> > * Implement auto-reconfiguration (if the configure script changes, you get
> >    an automatic reconfiguration instead of a message saying that you need to
> >    do so.)
> > * Implement auto update of Makefile.config (if you change Makefile.config.in
> >    it automatically gets regenerated to Makefile.config)
> > * Added tblgen build rules to Makefile.rules and removed from the X86 and
> >    PPC target Makefiles. There was some overlap. Standardizing these will
> >    encourage future targets to use them. These rules are available if you set
> >    the TARGET variable.
> > * $(DEST*) variables are gone unless they specifically refer to the
> >    installation destination. These conflicted with standard makefile usage
> > * $(BUILD_OBJ_DIR)/$(CONFIGURATION) became $(OBJDIR) to simplify it. This is
> >    where object files should go.
> > * $(LIBDIR) is where libraries should go
> > * $(TOOLDIR) is where tools (executables) should go
> > * VERBOSE=1 mode is now even quieter (a few rules were missing $(VERB)
> > * Build messages have been corrected and made more indicative
> > * The "prdirs" target has been replaced with the "printvars" target which
> >    prints values for interesting make variables, not just the directories.
> >
> > Brian: I've emailed your one Makefile change that you need to use in
> > WholeReoptimizer library after you take the Makefile.rules update.
> >
> > Alkis: Some very minor changes were needed in your Java project, but since I
> > don't have access to your cvs repository any more, I can't tell you what
> > changed (my file timestamps are all the same for some reason). So, try building
> > it, if it isn't obvious what's wrong, let me know.
> >
> > Misha/Brian: I didn't try compiling LLVM-TV with this, but I doubt you'll run
> > into any significant problems, the user changes are few
> >
> > Everyone: llvm-test has successfully compiled and run ONCE with these changes.
> > However, please note that llvm-test no longer depends on llvm/Makefile.rules. I
> > copied the OLD Makefile.rules to llvm-test/Makefile.rules.  The ONLY remaining
> > dependency between llvm-test and llvm proper is the Makefile.confg(.in) file.
> > This was the only "safe/quick" way to ensure I didn't break llvm-test.  As time
> > goes on we need to straighten out the Makefile mess in llvm-test but that's
> > another project.
> >
> > Reid.
> >
> > _______________________________________________
> > LLVM Developers mailing list
> > LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> > http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev
> >
> 
> 
> --
> Michael McCracken
> UCSD CSE PhD Student
> San Diego Supercomputer Center
> http://www.cse.ucsd.edu/~mmccrack/
> 


-- 
Michael McCracken
UCSD CSE PhD Student
San Diego Supercomputer Center
http://www.cse.ucsd.edu/~mmccrack/