btrfs-progs: build: add basic support for subdirectory build

Add explicit target file names and set the top source directory.

Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/Makefile.in b/Makefile.in
index 214b042..7202cdb 100644 (file)
--- a/Makefile.in
+++ b/Makefile.in
@@ -51,6 +51,8 @@ DEBUG_CFLAGS_DEFAULT = -O0 -U_FORTIFY_SOURCE -ggdb3
 DEBUG_CFLAGS_INTERNAL =
 DEBUG_CFLAGS :=
 
+TOPDIR := $(shell pwd)
+
 # Common build flags
 CFLAGS = @CFLAGS@ \
         -include config.h \
@@ -58,6 +60,7 @@ CFLAGS = @CFLAGS@ \
         -D_XOPEN_SOURCE=700  \
         -fno-strict-aliasing \
         -fPIC \
+        -I$(TOPDIR) \
         $(EXTRAWARN_CFLAGS) \
         $(DEBUG_CFLAGS_INTERNAL) \
         $(EXTRA_CFLAGS)
@@ -231,7 +234,7 @@ else
 endif
 
 %.o.d: %.c
-       $(Q)$(CC) -MM -MG -MF $@ -MT $(@:.o.d=.o) -MT $(@:.o.d=.static.o) -MT $@ $(CFLAGS) $<
+       $(Q)$(CC) -MD -MM -MG -MF $@ -MT $(@:.o.d=.o) -MT $(@:.o.d=.static.o) -MT $@ $(CFLAGS) $<
 
 #
 # Pick from per-file variables, btrfs_*_cflags
@@ -240,7 +243,7 @@ endif
        @$(check_echo) "    [SP]     $<"
        $(Q)$(check) $(CFLAGS) $(CHECKER_FLAGS) $<
        @echo "    [CC]     $@"
-       $(Q)$(CC) $(CFLAGS) -c $< $($(subst -,_,$(@:%.o=%)-cflags))
+       $(Q)$(CC) $(CFLAGS) -c $< -o $@ $($(subst -,_,$(@:%.o=%)-cflags))
 
 %.static.o: %.c
        @echo "    [CC]     $@"