[PATCH] Improve bootstrap times

[Richard Biener]

On Thu, 26 Apr 2018, Richard Biener wrote:

> On Thu, 26 Apr 2018, Bernhard Reutner-Fischer wrote:
> 
> > On 25 April 2018 16:11:23 CEST, Richard Biener <rguenther@suse.de> wrote:
> > >On Wed, 25 Apr 2018, Jakub Jelinek wrote:
> > >
> > >> On Wed, Apr 25, 2018 at 03:52:28PM +0200, Richard Biener wrote:
> > >> > Forcefully setting STAGE3_[CT]FLAGS doesn't have any effect on
> > >> > a checking enabled build but it will disrupt profiledbootstrap
> > >> > on a release build by training with -fchecking.  Suggestions
> > >> > welcome - not sure whether adjusting STAGE3_[CT]FLAGS after
> > >> > setting STAGEtrain_[CT]FLAGS will have the desired effect of
> > >> > leaving the latter alone.
> > >> 
> > >> You could perhaps replace
> > >> STAGEtrain_CFLAGS = $(STAGE3_CFLAGS)
> > >> STAGEtrain_TFLAGS = $(STAGE3_TFLAGS)
> > >> with
> > >> STAGEtrain_CFLAGS = $(filter-out -fchecking,$(STAGE3_CFLAGS))
> > >> STAGEtrain_TFLAGS = $(filter-out -fchecking,$(STAGE3_TFLAGS))
> > >> ?
> > >
> > >Good idea - I'll check if that works.
> > 
> > Is filter-out guaranteed to be supported on anything other than GNU make?
> 
> We use it elsewhere already.

Ok, so the following passed bootstrap & profiledbootstrap (and I checked
we only get -fno-checking at the appropriate places and not -fchecking)
on trunk, a bootstrap with all languages and release checking is running
(just to see whether no-checking but -fchecking during stage3 uncovers
any latent issue).

OK for trunk?

Thanks,
Richard.

2018-04-26  Richard Biener  <rguenther@suse.de>

	* Makefile.tpl (STAGE1_TFLAGS): Add -fno-checking.
	(STAGE2_CFLAGS): Likewise.
	(STAGE2_TFLAGS): Likewise.
	(STAGE3_CFLAGS): Add -fchecking.
	(STAGE3_TFLAGS): Likewise.
	(STAGEtrain_CFLAGS): Filter out -fchecking.
	(STAGEtrain_TFLAGS): Likewise.
	* Makefile.in: Re-generate.

Index: Makefile.tpl
===================================================================
--- Makefile.tpl	(revision 259638)
+++ Makefile.tpl	(working copy)
@@ -452,11 +452,21 @@ STAGE1_CONFIGURE_FLAGS = --disable-inter
 	  --disable-coverage --enable-languages="$(STAGE1_LANGUAGES)" \
 	  --disable-build-format-warnings
 
+# When using the slow stage1 compiler disable IL verification and forcefully
+# enable it when using the stage2 compiler instead.  As we later compare
+# stage2 and stage3 we are merely avoid doing redundant work, plus we apply
+# checking when building all target libraries for release builds.
+STAGE1_TFLAGS += -fno-checking
+STAGE2_CFLAGS += -fno-checking
+STAGE2_TFLAGS += -fno-checking
+STAGE3_CFLAGS += -fchecking
+STAGE3_TFLAGS += -fchecking
+
 STAGEprofile_CFLAGS = $(STAGE2_CFLAGS) -fprofile-generate
 STAGEprofile_TFLAGS = $(STAGE2_TFLAGS)
 
-STAGEtrain_CFLAGS = $(STAGE3_CFLAGS)
-STAGEtrain_TFLAGS = $(STAGE3_TFLAGS)
+STAGEtrain_CFLAGS = $(filter-out -fchecking,$(STAGE3_CFLAGS))
+STAGEtrain_TFLAGS = $(filter-out -fchecking,$(STAGE3_TFLAGS))
 
 STAGEfeedback_CFLAGS = $(STAGE4_CFLAGS) -fprofile-use
 STAGEfeedback_TFLAGS = $(STAGE4_TFLAGS)
Index: Makefile.in
===================================================================
--- Makefile.in	(revision 259638)
+++ Makefile.in	(working copy)
@@ -529,11 +529,21 @@ STAGE1_CONFIGURE_FLAGS = --disable-inter
 	  --disable-coverage --enable-languages="$(STAGE1_LANGUAGES)" \
 	  --disable-build-format-warnings
 
+# When using the slow stage1 compiler disable IL verification and forcefully
+# enable it when using the stage2 compiler instead.  As we later compare
+# stage2 and stage3 we are merely avoid doing redundant work, plus we apply
+# checking when building all target libraries for release builds.
+STAGE1_TFLAGS += -fno-checking
+STAGE2_CFLAGS += -fno-checking
+STAGE2_TFLAGS += -fno-checking
+STAGE3_CFLAGS += -fchecking
+STAGE3_TFLAGS += -fchecking
+
 STAGEprofile_CFLAGS = $(STAGE2_CFLAGS) -fprofile-generate
 STAGEprofile_TFLAGS = $(STAGE2_TFLAGS)
 
-STAGEtrain_CFLAGS = $(STAGE3_CFLAGS)
-STAGEtrain_TFLAGS = $(STAGE3_TFLAGS)
+STAGEtrain_CFLAGS = $(filter-out -fchecking,$(STAGE3_CFLAGS))
+STAGEtrain_TFLAGS = $(filter-out -fchecking,$(STAGE3_TFLAGS))
 
 STAGEfeedback_CFLAGS = $(STAGE4_CFLAGS) -fprofile-use
 STAGEfeedback_TFLAGS = $(STAGE4_TFLAGS)