From efc9511cecf617c828734024f4e1cde5f974f510 Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Tue, 13 Oct 2020 16:53:16 -0700 Subject: selftests/vm: fix false build success on the second and later attempts Patch series "selftests/vm: fix some minor aggravating factors in the Makefile". This fixes a couple of minor aggravating factors that I ran across while trying to do some changes in selftests/vm. These are simple things, but like most things with GNU Make, it's rarely obvious what's wrong until you understand *the entire Makefile and all of its includes*. So while there is, of course, joy in learning those details, I thought I'd fix these little things, so as to allow others to skip out on the Joy if they so choose. :) First of all, if you have an item (let's choose userfaultfd for an example) that fails to build, you might do this: $ make -j32 # ...you observe a failed item in the threaded output # OK, let's get a closer look $ make # ...but now the build quietly "succeeds". That's what Patch 0001 fixes. Second, if you instead attempt this approach for your closer look (a casual mistake, as it's not supported): $ make userfaultfd # ...userfaultfd fails to link, due to incomplete LDLIBS That's what Patch 0002 fixes. This patch (of 2): If one or more of these selftest fail to build, then after the first failure, subsequent invocations of "make" will make it appear that there are no build failures, after all. That's because the failed build products remain, with up-to-date timestamps, thus tricking Make (and you!) into believing that there's nothing else to build. Fix this by telling Make to delete targets that didn't completely succeed. Signed-off-by: John Hubbard Signed-off-by: Andrew Morton Cc: Shuah Khan Cc: Jason Gunthorpe Link: https://lkml.kernel.org/r/20200915012901.1655280-1-jhubbard@nvidia.com Link: https://lkml.kernel.org/r/20200915012901.1655280-2-jhubbard@nvidia.com Signed-off-by: Linus Torvalds --- tools/testing/selftests/vm/Makefile | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'tools/testing/selftests/vm/Makefile') diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index a9026706d597..9f2625bebf07 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -3,6 +3,11 @@ uname_M := $(shell uname -m 2>/dev/null || echo not) MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/') +# Without this, failed build products remain, with up-to-date timestamps, +# thus tricking Make (and you!) into believing that All Is Well, in subsequent +# make invocations: +.DELETE_ON_ERROR: + CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS) LDLIBS = -lrt TEST_GEN_FILES = compaction_test -- cgit v1.2.3-59-g8ed1b