Hello, I just completed a test build with my patch to arch/m68k/Makefile to remove the -pipe flag (see patch below). Watching the build confirmed that a) -pipe was no longer showing up in the gcc command lines and b) temporary files were being created as expected without pipe; and c) the as command was not loaded waiting for cc1 to complete. Yea! The /arch/m68k/Makefile is the only place where the -pipe flag is located, and that seems to be the place for all arch's.
--- arch/m68k/Makefile.old 2009-05-13 21:58:28.000000000 -0500 +++ arch/m68k/Makefile 2009-05-09 11:16:39.000000000 -0500 @@ -33,7 +33,9 @@ CHECKFLAGS += -D__mc68000__ # without -fno-strength-reduce the 53c7xx.c driver fails ;-( -KBUILD_CFLAGS += -pipe -fno-strength-reduce -ffixed-a2 +# delete -pipe to save RAM / minimize swap during compile +# original: KBUILD_CFLAGS += -pipe -fno-strength-reduce -ffixed-a2 +KBUILD_CFLAGS += -fno-strength-reduce -ffixed-a2 # enable processor switch if compiled only for a single cpu ifndef CONFIG_M68020 Pulling out the -pipe does seem to cut compile time. I am working on hard numbers. --Lance On Wed, May 13, 2009 at 02:38:29AM +0200, Sam Ravnborg wrote: > On Mon, May 11, 2009 at 08:02:16AM +0200, Geert Uytterhoeven wrote: > > Added linux-kbuild > > > > On Mon, May 11, 2009 at 03:58, Lance Tagliapietra <[email protected]> > > wrote: > > > I was noticing that kernel compiling is set up to have gcc pipe data from > > > one pass to another, instead of using > > > temporary files. ?On a memory constrained environment, this may not be > > > the best idea (or at least I'd like to > > > explore that idea). ?Instead of loading the assember, and having > > > immediately being swapped out while the cc1 pass > > > runs, it may make more sense to have the temp files being written, > > > instead of the swap in and out, when compiling > > > the various objects of the kernel. > > > > > > So, simply pulling out the -pipe from the compiler flag list didn't see > > > to have the desired effect. ?I'm afraid I'm > > > still missing something. ?I'm still observing the assembler being loaded. > > 1) How did you "pulling out the -pipe from the compiler flag list"? > Please show this as a patch. > > 2) Did you verify that -pipe was used before and no more after your > changes? > Hint - use "make V=1" to see all command line options to gcc > > Sam -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
