BSD Make substitution fails in rule $(objdir)/%o: %c

Question

I'm trying to write a portable BSD and GNU Makefile that does an out-of-source build and automatic prerequisites. GNU Make works fine but BSD Make does not.

OBJDIR := objdir
SRCS := foo.c bar.c baz.c
OBJS := $(SRCS:%.c=$(OBJDIR)/%.o)
CPPFLAGS += -MMD -MP

all: $(OBJDIR) $(OBJS)
    $(CC) $(LDFLAGS) -o main $(OBJS) $(LDLIBS)

$(OBJDIR)/%.o: %.c
    $(COMPILE.c) $(OUTPUT_OPTION) $<

$(OBJDIR):
    mkdir $(OBJDIR)

-include $(OBJDIR)/$(SRCS:%.c=%.d)

clean:
    rm -rf main $(OBJDIR)

This is the output:

$ gmake
mkdir objdir
cc  -MMD -MP  -c -o objdir/foo.o foo.c
cc  -MMD -MP  -c -o objdir/bar.o bar.c
cc  -MMD -MP  -c -o objdir/baz.o baz.c
cc  -o main objdir/foo.o objdir/bar.o objdir/baz.o
$ bmake
--- objdir ---
bmake: bmake: don't know how to make objdir/foo.o. Stop

bmake: stopped in /home/antonin/tests

My guess is that BSD Make does not understand substitution within a path (is that the right term?) $(OBJDIR)/%.o: %.c, because bmake OBJDIR=. works fine. If so, how can I write a simple, portable Makefile that achieves the same functionality?

Example for testing.

Thank you!