build: Deactivate implicit build make(1) rules.

[osl.git] / Makefile

diff --git a/Makefile b/Makefile
index 8e0f163b671aaba4554cfe76a00febaa99c24fa1..76ab5eb5a3192cd5daa72ceda4dc8fcd936ea7be 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,12 @@
+# Implicit rules are implemented in make as suffix rules. The following rule
+# empties the suffix list to disable the predefined implicit rules. This
+# increases performance and avoids hard-to-debug behaviour.
+.SUFFIXES:
+MAKEFLAGS += -Rr
+ifeq ("$(origin CC)", "default")
+       CC := cc
+endif
+
 # where to install
 PREFIX ?= /usr/local
 libdir := $(PREFIX)/lib
@@ -28,26 +37,25 @@ y := 1
 z := 3
 VERSION := $(x).$(y).$(z)
 
-# common flags
-CPPFLAGS += -DOSL_VERSION='"$(VERSION)"'
-
-CFLAGS += -Wno-sign-compare -g -Wunused -Wundef -W
-CFLAGS += -Wredundant-decls
-CFLAGS += -Os
-CFLAGS += -Wall
-CFLAGS += -Wuninitialized
-CFLAGS += -Wchar-subscripts
-CFLAGS += -Wformat-security
-CFLAGS += -Werror-implicit-function-declaration
-CFLAGS += -Wmissing-format-attribute
-CFLAGS += -Wunused-macros
-CFLAGS += -Wbad-function-cast
-CFLAGS += -fPIC
-CFLAGS += -fvisibility=hidden
-
-LDFLAGS += -Wl,-soname,$(soname)
-LDFLAGS += -Wl,-z,defs
-LDFLAGS += --shared
+OSL_CPPFLAGS += -DOSL_VERSION='"$(VERSION)"'
+
+OSL_CFLAGS += -Wno-sign-compare -g -Wunused -Wundef -W
+OSL_CFLAGS += -Wredundant-decls
+OSL_CFLAGS += -Os
+OSL_CFLAGS += -Wall
+OSL_CFLAGS += -Wuninitialized
+OSL_CFLAGS += -Wchar-subscripts
+OSL_CFLAGS += -Wformat-security
+OSL_CFLAGS += -Werror-implicit-function-declaration
+OSL_CFLAGS += -Wmissing-format-attribute
+OSL_CFLAGS += -Wunused-macros
+OSL_CFLAGS += -Wbad-function-cast
+OSL_CFLAGS += -fPIC
+OSL_CFLAGS += -fvisibility=hidden
+
+OSL_LDFLAGS += -Wl,-soname,$(soname)
+OSL_LDFLAGS += -Wl,-z,defs
+OSL_LDFLAGS += --shared
 
 # On ELf-based systems, the following conventions apply (see dhweeler's
 # Program Library HOWTO):
@@ -67,19 +75,25 @@ realname := $(soname).$(y).$(z)
 # soname without any version number.
 linkername := lib$(libname).so
 
-all: $(realname) $(executables) $(man_pages)
+all: $(realname) $(executables) $(man_pages) $(headers)
 shared: $(realname)
 
 ifeq ($(findstring clean, $(MAKECMDGOALS)),)
 -include $(deps)
 endif
-%.o: %.c Makefile errtab.h
-       $(CC) $(CPPFLAGS) -c -MMD -MF $(*F).d -MT $@ $(CFLAGS) $<
+
+# List osl.h in the prerequisites to make sure we generate it before attempting
+# to run the compiler. This matters only when the .d file does not exist.
+%.o: %.c osl.h Makefile errtab.h
+       $(CC) $(OSL_CPPFLAGS) $(CPPFLAGS) \
+               -c -MMD -MF $(*F).d -MT $@ \
+               $(OSL_CFLAGS) $(CFLAGS) $<
 
 fsck.o: oslfsck.lsg.h
 oslfsck: $(fsck_objects)
-       $(CC) -o $@ $(fsck_objects) -llopsub
+       $(CC) -o $@ $(fsck_objects) $(LDFLAGS) -llopsub
 
+.PRECIOUS: %.lsg.h %.lsg.c
 %.lsg.c: %.suite
        lopsubgen --gen-c < $<
 
@@ -90,34 +104,24 @@ oslfsck: $(fsck_objects)
        lopsubgen --gen-man=$@ < $<
 
 $(realname): $(objects)
-       $(CC) $(LDFLAGS) -o $@ $(objects)
-
-$(libname).sym: osl.h.in
-       sed -Ene '/^int|^const/{s/.*(osl_.*)\(.*/\1/; p;}' $< > $@
-$(libname).ga: $(objects)
-       $(LD) -r -o $@ $(objects)
-lib$(libname).a: $(libname).ga $(libname).sym
-       $(OBJCOPY) --keep-global-symbols $(libname).sym $(libname).ga $@
-
-osl_errors.h: errlist
-       echo '/** public error codes of the osl library. */' > $@
-       sed -e 's/\([A-Z_]*\)   .*/     E_OSL_\1/' \
-               -e '1s/^/enum osl_errors {/1' \
-               -e '1s/$$/=1/1' \
-               -e '$$!s/$$/,/g' \
-               -e '$$s/$$/};/1' $< >> $@
+       $(CC) $(OSL_LDFLAGS) $(LDFLAGS) -o $@ $(objects)
 
 errtab.h: errlist
        sed -e 's/^\([A-Z_]*\)\s*\(.*\)/OSL_ERROR(E_OSL_\1, \2)/g' $< > $@
 
-osl.h: osl.h.in osl_errors.h Makefile
+osl.h: osl.h.in errlist Makefile
        echo '#ifndef _OSL_H' > $@
        echo '#define _OSL_H' >> $@
-       cat osl.h.in osl_errors.h >> $@
+       cat osl.h.in >> $@
+       echo '/** public error codes of the osl library. */' >> $@
+       sed -e 's/\([A-Z_]*\)   .*/     E_OSL_\1/' \
+               -e '1s/^/enum osl_errors {/1' \
+               -e '1s/$$/=1/1' \
+               -e '$$!s/$$/,/g' \
+               -e '$$s/$$/};/1' errlist >> $@
        echo '#endif /* _OSL_H */' >> $@
 clean:
-       rm -f *.o $(realname) osl.h osl_errors.h errtab.h \
-               oslfsck *.a *.ga *.sym *.lsg.* *.d
+       rm -f *.o $(realname) osl.h errtab.h oslfsck *.lsg.* *.d
 
 distclean: clean
        rm -f web/index.html web/oslfsck.1.html web/osl.png