fix file copy

The copy for bits.h ran in parallel with the initial CC.  sometimes on
CI the build would fail as the file had not arrived by the time
needed.  Fix matches meson build process.

.gitignore

@@ -1,4 +1,3 @@
-include/libucontext/bits.h
 *.o
 examples/cooperative_threading
 test_libucontext

Makefile

@@ -36,7 +36,9 @@ FREESTANDING := no
 
 ifeq ($(FREESTANDING),yes)
 	CPPFLAGS += -DFREESTANDING
-	EXPORT_UNPREFIXED = no
+	EXPORT_UNPREFIXED = no -Iarch/${ARCH}/include
+else
+	CPPFLAGS += -Iarch/common/include
 endif
 
 FORCE_SOFT_FLOAT := no
@@ -86,8 +88,12 @@ LIBUCONTEXT_PC = libucontext.pc
 LIBUCONTEXT_PATH = ${shared_libdir}/${LIBUCONTEXT_SONAME}
 LIBUCONTEXT_STATIC_PATH = ${static_libdir}/${LIBUCONTEXT_STATIC_NAME}
 LIBUCONTEXT_HEADERS = \
-	include/libucontext/libucontext.h \
-	include/libucontext/bits.h
+	include/libucontext/libucontext.h
+ifeq ($(FREESTANDING),yes)
+LIBUCONTEXT_HEADERS += arch/${ARCH}/include/libucontext/bits.h
+else
+LIBUCONTEXT_HEADERS += arch/common/include/libucontext/bits.h
+endif
 LIBUCONTEXT_EXAMPLES = \
 	examples/cooperative_threading
 LIBUCONTEXT_POSIX_STATIC_NAME = libucontext_posix.a
@@ -112,10 +118,10 @@ ${LIBUCONTEXT_POSIX_STATIC_NAME}: ${LIBUCONTEXT_STATIC_NAME} ${LIBUCONTEXT_POSIX
 ${LIBUCONTEXT_POSIX_SONAME}: ${LIBUCONTEXT_POSIX_NAME}
 	ln -sf ${LIBUCONTEXT_POSIX_NAME} ${LIBUCONTEXT_POSIX_SONAME}
 
-${LIBUCONTEXT_STATIC_NAME}: ${LIBUCONTEXT_HEADERS} ${LIBUCONTEXT_OBJ}
+${LIBUCONTEXT_STATIC_NAME}: ${LIBUCONTEXT_OBJ}
 	$(AR) rcs ${LIBUCONTEXT_STATIC_NAME} ${LIBUCONTEXT_OBJ}
 
-${LIBUCONTEXT_NAME}: ${LIBUCONTEXT_HEADERS} ${LIBUCONTEXT_OBJ}
+${LIBUCONTEXT_NAME}: ${LIBUCONTEXT_OBJ}
 	$(CC) -fPIC -o ${LIBUCONTEXT_NAME} ${LIBUCONTEXT_LINKER_FLAGS} ${LIBUCONTEXT_OBJ} ${LDFLAGS}
 
 ${LIBUCONTEXT_SONAME}: ${LIBUCONTEXT_NAME}
@@ -164,9 +170,6 @@ libucontext_obj_clean:
 ${LIBUCONTEXT_PC}_clean:
 	rm -f ${LIBUCONTEXT_PC}
 
-bits_clean:
-	rm -f include/libucontext/bits.h
-
 ${LIBUCONTEXT_POSIX_NAME}_clean:
 	rm -f ${LIBUCONTEXT_POSIX_NAME}
 
@@ -197,7 +200,6 @@ clean: ${LIBUCONTEXT_NAME}_clean
 clean: ${LIBUCONTEXT_SONAME}_clean
 clean: ${LIBUCONTEXT_STATIC_NAME}_clean
 clean: ${LIBUCONTEXT_PC}_clean
-clean: bits_clean
 clean: ${LIBUCONTEXT_POSIX_NAME}_clean
 clean: ${LIBUCONTEXT_POSIX_SONAME}_clean
 clean: ${LIBUCONTEXT_POSIX_STATIC_NAME}_clean
@@ -258,18 +260,6 @@ examples: ${LIBUCONTEXT_EXAMPLES}
 examples/cooperative_threading: examples/cooperative_threading.c ${LIBUCONTEXT_NAME}
 	$(CC) -std=gnu99 -D_BSD_SOURCE ${CFLAGS} ${CPPFLAGS} $@.c -o $@ -L. -lucontext
 
-ifeq ($(FREESTANDING),no)
-
-include/libucontext/bits.h: arch/common/include/libucontext/bits.h
-	cp $< $@
-
-else
-
-include/libucontext/bits.h: arch/${ARCH}/include/libucontext/bits.h
-	cp $< $@
-
-endif
-
 PACKAGE_NAME = libucontext
 PACKAGE_VERSION = ${LIBUCONTEXT_VERSION}
 DIST_NAME = ${PACKAGE_NAME}-${PACKAGE_VERSION}