From 98a07006c48dc0bc3f42b3b3ce75b7f03e87e724 Mon Sep 17 00:00:00 2001 From: Sergei Trofimovich Date: Sun, 25 Sep 2022 11:42:03 +0100 Subject: [PATCH] Makefile: fix infinite recursion by dropping non-existent `%.output` Without the change GNU `make-4.4` falls into infinite recursion of trying to generate %.output files (bison is not passed flags to generate debug output). This happens on GNU `make-4.4` only after GNU make change to more eagerly rebuild all target outputs in multiple targets: https://savannah.gnu.org/bugs/index.php?63098 The recursion here is the following: - Makefile depends on *.d files - *.d files depend on *.c files - *.c files are generated by bison - bison is triggered whenever some of it's multiple targets are missing In our case `%.output` is always missing and bison is always reran. *.d files are always regenerated on `make` run. And make is always restarted as *.d files are always regenerated. The fix removes infeasible `%.output`. Signed-off-by: Sergei Trofimovich Message-Id: <20220925104203.648449-2-slyich@gmail.com> Signed-off-by: David Gibson --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index e7a0dcb..d4e7551 100644 --- a/Makefile +++ b/Makefile @@ -384,7 +384,7 @@ clean: libfdt_clean pylibfdt_clean tests_clean @$(VECHO) LEX $@ $(LEX) -o$@ $< -%.tab.c %.tab.h %.output: %.y +%.tab.c %.tab.h: %.y @$(VECHO) BISON $@ $(BISON) -b $(basename $(basename $@)) -d $<