[ was: Re: [RFC] Prevent unnecessary recompilation for trivial
params.def changes ]
On 08/09/15 14:03, Andreas Schwab wrote:
Tom de Vries <tom_devr...@mentor.com> writes:
After a subsequent rebuild I don't see anything being rebuild. So I don't
observe 'continuous rebuilding'.
What happens when you just touch params-list.h or params.def?
move-if-change will leave the target untouched when unchanged (that's
the whole point of it), so it will remain older than the dependencies.
I could reproduce the problem using these instructions, thanks.
I also found a bit "On the use of stamps" in gcc/Makefile.in, which
explains the problem and how to fix things.
Updated patch accordingly.
OK for trunk if bootstrap succeeds?
Thanks,
- Tom
Prevent unnecessary recompilation for trivial params.def changes
2015-09-08 Tom de Vries <t...@codesourcery.com>
* Makefile.in (generated_files): Add params.list.
(params.list, s-params.list): Add rule.
* params.h (enum compiler_param): Include params-list.h. Move define
DEFPARAM, include params.def and undef DEFPARAM ...
* params-list.h: ... here. New file.
---
gcc/Makefile.in | 8 +++++++-
gcc/params-list.h | 4 ++++
gcc/params.h | 5 +----
3 files changed, 12 insertions(+), 5 deletions(-)
create mode 100644 gcc/params-list.h
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 3d1c1e5..b495bd2 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -2415,7 +2415,7 @@ generated_files = config.h tm.h $(TM_P_H) $(TM_H) multilib.h \
$(ALL_GTFILES_H) gtype-desc.c gtype-desc.h gcov-iov.h \
options.h target-hooks-def.h insn-opinit.h \
common/common-target-hooks-def.h pass-instances.def \
- c-family/c-target-hooks-def.h
+ c-family/c-target-hooks-def.h params.list
#
# How to compile object files to run on the build machine.
@@ -3236,6 +3236,12 @@ installdirs:
$(mkinstalldirs) $(DESTDIR)$(man1dir)
$(mkinstalldirs) $(DESTDIR)$(man7dir)
+params.list: s-params.list; @true
+s-params.list: $(srcdir)/params-list.h $(srcdir)/params.def
+ $(CPP) $(srcdir)/params-list.h | sed 's/^#.*//;/^$$/d' > tmp-params.list
+ $(SHELL) $(srcdir)/../move-if-change tmp-params.list params.list
+ $(STAMP) s-params.list
+
PLUGIN_HEADERS = $(TREE_H) $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
toplev.h $(DIAGNOSTIC_CORE_H) $(BASIC_BLOCK_H) $(HASH_TABLE_H) \
tree-ssa-alias.h $(INTERNAL_FN_H) gimple-fold.h tree-eh.h gimple-expr.h \
diff --git a/gcc/params-list.h b/gcc/params-list.h
new file mode 100644
index 0000000..49301d2
--- /dev/null
+++ b/gcc/params-list.h
@@ -0,0 +1,4 @@
+#define DEFPARAM(enumerator, option, nocmsgid, default, min, max) \
+ enumerator,
+#include "params.def"
+#undef DEFPARAM
diff --git a/gcc/params.h b/gcc/params.h
index f53426d..9f7618a 100644
--- a/gcc/params.h
+++ b/gcc/params.h
@@ -81,10 +81,7 @@ extern void set_param_value (const char *name, int value,
enum compiler_param
{
-#define DEFPARAM(enumerator, option, nocmsgid, default, min, max) \
- enumerator,
-#include "params.def"
-#undef DEFPARAM
+#include "params.list"
LAST_PARAM
};
--
1.9.1
