tools: testing: support EXTRA_CFLAGS in shared.mk

This allows the user to set cflags when building tests that use this
shared build infrastructure.

For example, it enables building with -Werror so that patch-check scripts
will fail:

	make -C tools/testing/vma -j EXTRA_CFLAGS=-Werror

Link: https://lkml.kernel.org/r/20250828-b4-vma-no-atomic-h-v2-3-02d146a58ed2@google.com
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: Pedro Falcato <pfalcato@suse.de>
Cc: Jann Horn <jannh@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/tools/testing/shared/shared.mk b/tools/testing/shared/shared.mk
index 937aaa7623320da1085a8e0f43f6a728ddd3ab1c..5bcdf26c8a9d51ab2cbd264f2f8a7445d7c036e3 100644 (file)
--- a/tools/testing/shared/shared.mk
+++ b/tools/testing/shared/shared.mk
@@ -4,6 +4,7 @@ include ../../scripts/Makefile.arch
 CFLAGS += -I../shared -I. -I../../include -I../../arch/$(SRCARCH)/include \
          -I../../../lib -g -Og -Wall \
          -D_LGPL_SOURCE -fsanitize=address -fsanitize=undefined
+CFLAGS += $(EXTRA_CFLAGS)
 LDFLAGS += -fsanitize=address -fsanitize=undefined
 LDLIBS += -lpthread -lurcu
 LIBS := slab.o find_bit.o bitmap.o hweight.o vsprintf.o