build-cpp-and-ld-flags

[BUILD] CPPFLAGS, CFLAGS and LDFLAGS fixes

* Set internal CPPFLAGS as EXTRA_CPPFLAGS, CFLAGS as EXTRA_CFLAGS,
  and LDFLAGS as EXTRA_LDFLAGS
  - Don't overwrite CPPFLAGS, LDLFAGS or CFLAGS from the environment
  - They are irrelevant for BUILD_CC
  - When cross-compiling for a ppc64 host on a non-ppc64 host,
    EXTRA_CFLAGS, which is included in BUILD_CPPFLAGS contains
  -mcall-aixdesc, which does not work on i386 at least
* Use LDFLAGS when linking kexec
  - Append rather than overwrite in purgatory/Makefile

The purpose of these changes is three-fold.

  * CPPFLAGS, CFLAGS and LDFLAGS from the environment really ought
    to be honoured. For one thing;
  * Without these changes, the confgiure taget in
    the toplevel makefile can't work
  * Without these changes, cross compiling does not work -
    well, I can't work out how to get it to work anyway.

Signed-Off-By: Simon Horman <horms@verge.net.au>

7 files changed, 20 insertions, 21 deletions

diff --git a/Makefile b/Makefile
index efa8799..db72776 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,7 @@ pkgincludedir = $(includedir)/$(PACKAGE)
 # Useful for building binary packages
 DESTDIR =
 
-CPPFLAGS:= -I./include -I./util_lib/include \
+EXTRA_CPPFLAGS:= -I./include -I./util_lib/include \
 	-DVERSION='"$(VERSION)"' -DRELEASE_DATE='"$(DATE)"' \
 	$(DEFS) $(EXTRA_CFLAGS)
 
@@ -54,8 +54,9 @@ all: $(TARGETS)
 
 # cc-option
 # Usage: cflags-y += $(call cc-option, -march=winchip-c6, -march=i586)
-cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
-             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
+cc-option = $(shell if $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(1) -S -o /dev/null \
+	     -xc /dev/null > /dev/null 2>&1; then echo "$(1)"; else \
+	     echo "$(2)"; fi ;)
 
 # Utility function library
 #
diff --git a/configure.ac b/configure.ac
index af8d9c7..7c72845 100644
--- a/configure.ac
+++ b/configure.ac
@@ -50,7 +50,9 @@ OBJDIR=`pwd`/objdir
 if test "${host_alias}" ; then
 	OBJDIR="$OBJDIR-${host_alias}"
 fi 
-EXTRA_CFLAGS=""
+
+EXTRA_CFLAGS='-Wall -g -fno-strict-aliasing $(CPPFLAGS) $(EXTRA_CPPFLAGS)'
+BUILD_CFLAGS='-O2 -Wall $(CPPFLAGS)'
 
 # Check whether ppc64. Add -m64 for building 64-bit binary
 # Add -mcall-aixdesc to generate dot-symbols as in gcc 3.3.3
@@ -104,11 +106,6 @@ if test "$with_zlib" = yes ; then
 	AC_CHECK_HEADER(zlib.h, AC_CHECK_LIB(z, inflateInit_, [AC_DEFINE(HAVE_ZLIB_H, 1) LIBS="$LIBS -lz"]))
 fi
 
-dnl ---Hard codes
-
-CFLAGS='-Wall -g -fno-strict-aliasing $(CPPFLAGS)'
-BUILD_CFLAGS='-O2 -Wall $(CPPFLAGS)'
-
 dnl ---Sanity checks
 if test "$CC"      = "no"; then AC_MSG_ERROR([cc not found]) fi
 if test "$CPP"     = "no"; then AC_MSG_ERROR([cpp not found]) fi
diff --git a/kdump/Makefile b/kdump/Makefile
index af33dc3..456c2fc 100644
--- a/kdump/Makefile
+++ b/kdump/Makefile
@@ -16,15 +16,15 @@ include $(KDUMP_DEPS)
 
 $(KDUMP_C_DEPS): $(OBJDIR)/%.d: %.c
 	mkdir -p $(@D)
-	$(CC) $(CFLAGS) -M $< | sed -e 's|$(patsubst %.d,%.o,$(@F))|$(patsubst %.d,%.o,$(@))|' > $@
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) -M $< | sed -e 's|$(patsubst %.d,%.o,$(@F))|$(patsubst %.d,%.o,$(@))|' > $@
 
 $(KDUMP_C_OBJS): $(OBJDIR)/%.o: %.c $(OBJDIR)/%.d
 	mkdir -p $(@D)
-	$(CC) $(CFLAGS) -o $@ -c $<
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) -o $@ -c $<
 
 $(KDUMP): $(KDUMP_OBJS)
 	mkdir -p $(@D)
-	$(CC) $(CFLAGS) -o $@ $(KDUMP_OBJS)
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) -o $@ $(KDUMP_OBJS)
 
 $(KDUMP_MANPAGE): kdump/kdump.8
 	$(MKDIR) -p     $(MANDIR)/man8
diff --git a/kexec/Makefile b/kexec/Makefile
index 3d906a6..000c1bb 100644
--- a/kexec/Makefile
+++ b/kexec/Makefile
@@ -7,7 +7,7 @@ $(PURGATORY_HEX_C): $(PURGATORY) $(BIN_TO_HEX)
 	$(MKDIR) -p $(@D)
 	$(BIN_TO_HEX) purgatory < $(PURGATORY) > $@
 
-KCFLAGS:= $(CFLAGS) -Ikexec/arch/$(ARCH)/include
+KCFLAGS:= $(CFLAGS) $(EXTRA_CFLAGS) -Ikexec/arch/$(ARCH)/include
 
 KEXEC_C_SRCS:= kexec/kexec.c 
 KEXEC_C_SRCS+= kexec/ifdown.c
@@ -68,7 +68,8 @@ $(KEXEC_S_OBJS): $(OBJDIR)/%.o: %.S $(OBJDIR)/%.d
 
 $(KEXEC): $(KEXEC_OBJS) $(UTIL_LIB)
 	mkdir -p $(@D)
-	$(CC) $(KCFLAGS) -o $@ $(KEXEC_OBJS) $(UTIL_LIB) $(LIBS)
+	$(CC) $(LDFLAGS) $(EXTRA_LDFLAGS) $(KCFLAGS) -o $@ \
+		$(KEXEC_OBJS) $(UTIL_LIB) $(LIBS)
 
 $(KEXEC_MANPAGE): kexec/kexec.8
 	 $(MKDIR) -p     $(MANDIR)/man8
diff --git a/kexec_test/Makefile b/kexec_test/Makefile
index 3e932d5..70542de 100644
--- a/kexec_test/Makefile
+++ b/kexec_test/Makefile
@@ -15,11 +15,11 @@ include $(KEXEC_TEST_DEPS)
 
 $(KEXEC_TEST_S_DEPS): $(OBJDIR)/%.d: %.S
 	mkdir -p $(@D)
-	$(CC) -m32 $(CFLAGS) -M $< | sed -e 's|$(patsubst %.d,%.o,$(@F))|$(patsubst %.d,%.o,$(@))|' > $@
+	$(CC) -m32 $(CFLAGS) $(EXTRA_CFLAGS) -M $< | sed -e 's|$(patsubst %.d,%.o,$(@F))|$(patsubst %.d,%.o,$(@))|' > $@
 
 $(KEXEC_TEST_S_TEMPS): $(OBJDIR)/%.s: %.S 
 	mkdir -p $(@D)
-	$(CPP) $(CPPFLAGS) -DRELOC=$(RELOC) $< > $@
+	$(CPP) $(CPPFLAGS) $(EXTRA_CPPFLAGS) -DRELOC=$(RELOC) $< > $@
 
 $(KEXEC_TEST_S_OBJS): $(OBJDIR)/%.o: $(OBJDIR)/%.s 
 	mkdir -p $(@D)
diff --git a/purgatory/Makefile b/purgatory/Makefile
index 50ce99f..adbd814 100644
--- a/purgatory/Makefile
+++ b/purgatory/Makefile
@@ -8,13 +8,13 @@
 # or headers.
 
 ifeq ($(ARCH),ppc64)
-LDFLAGS = -melf64ppc
+EXTRA_LDFLAGS = -melf64ppc
 endif
 
 PCFLAGS:=-Wall -Os  \
 	-I$(shell $(CC) -print-file-name=include) \
 	-Ipurgatory/include -Ipurgatory/arch/$(ARCH)/include \
-	$(CPPFLAGS)
+	$(CPPFLAGS) $(EXTRA_CPPFLAGS)
 
 PCFLAGS += $(call cc-option, -ffreestanding)
 PCFLAGS += $(call cc-option, -fnobuiltin)
@@ -59,7 +59,7 @@ $(PURGATORY_S_OBJS): $(OBJDIR)/%.o: %.S $(OBJDIR)/%.d
 
 $(PURGATORY): $(PURGATORY_OBJS) $(UTIL_LIB)
 	$(MKDIR) -p $(@D)
-	$(LD) $(LDFLAGS) --no-undefined -e purgatory_start -r -o $@ $(PURGATORY_OBJS) $(UTIL_LIB)
+	$(LD) $(LDFLAGS) $(EXTRA_LDFLAGS) --no-undefined -e purgatory_start -r -o $@ $(PURGATORY_OBJS) $(UTIL_LIB)
 
 echo::
 	@echo "PURGATORY_C_SRCS $(PURGATORY_C_SRCS)"
diff --git a/util_lib/Makefile b/util_lib/Makefile
index 4e1a01d..84679a1 100644
--- a/util_lib/Makefile
+++ b/util_lib/Makefile
@@ -11,11 +11,11 @@ include $(UTIL_LIB_DEPS)
 
 $(UTIL_LIB_DEPS): $(OBJDIR)/%.d: %.c 
 	$(MKDIR) -p $(@D)
-	$(CC) $(CFLAGS) -M $< | sed -e 's|$(patsubst %.d,%.o,$(@F))|$(patsubst %.d,%.o,$(@))|' > $@
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) -M $< | sed -e 's|$(patsubst %.d,%.o,$(@F))|$(patsubst %.d,%.o,$(@))|' > $@
 
 $(UTIL_LIB_OBJS): $(OBJDIR)/%.o: %.c $(OBJDIR)/%.d
 	$(MKDIR) -p $(@D)
-	$(CC) $(CFLAGS) -c -o $@ $<
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) -c -o $@ $<
 
 $(UTIL_LIB): $(UTIL_LIB_OBJS)
 	$(MKDIR) -p $(@D)