make: fix CPU reset in some conditions

In some cases like trying to build a package with debug config
(e.g. make cfg mode=debug; .... ; make deb), the CPU make variable
was reset resulting in a build failure. This happens because in
the debug config CPU is not set and hence is  saved as empty.
Trying to build a package will start a sub-make which will try to
re-do the config without debugging (make cfg), but the CPU
variable with and empty value will be inherited from the
environment and thus the CPU?=something lines won't have any
effect.
The fix replaces CPU?=something with
$(call set_if_empty,CPU,something)
This works around having an empty CPU in the environment.

Reported-by: Jan Janak  <jan@iptel.org>

diff --git a/Makefile.defs b/Makefile.defs
index a775bd9..1eb19f5 100644 (file)
--- a/Makefile.defs
+++ b/Makefile.defs
@@ -115,8 +115,11 @@ ifeq ($(quiet),verbose)
 $(info normal Makefile.defs exec)
 endif # verbose
 
+# usage: $(call set_if_empty,VAR,value)
+set_if_empty=$(if $($(1)),,$(eval override $(1)=$(2)))
+
 # flavour: sip-router, ser or kamailio
-FLAVOUR?=sip-router
+$(call set_if_empty,FLAVOUR,sip-router)
 
 #prefix for various configs and scripts
 #config name/name-prefix for distributed configs
@@ -816,7 +819,7 @@ ifeq                ($(CC_NAME), gcc)
                                CFLAGS=-g -O9 -funroll-loops  -Wcast-align $(PROFILE)
                        #if gcc 4.2+
 ifeq                   ($(CC_SHORTVER), 4.2+)
-                                       CPU ?= athlon64
+$(call                         set_if_empty,CPU,athlon64)
                                        CFLAGS+=-m32 -minline-all-stringops \
                                                        -falign-loops \
                                                        -ftree-vectorize \
@@ -826,7 +829,7 @@ ifeq                        ($(CC_SHORTVER), 4.2+)
 else
                        #if gcc 4.0+
 ifeq                   ($(CC_SHORTVER), 4.x)
-                                       CPU ?= athlon64
+$(call                         set_if_empty,CPU,athlon64)
                                        CFLAGS+=-m32 -minline-all-stringops \
                                                        -falign-loops \
                                                        -ftree-vectorize \
@@ -835,7 +838,7 @@ ifeq                        ($(CC_SHORTVER), 4.x)
 else
                        #if gcc 3.4+
 ifeq                   ($(CC_SHORTVER), 3.4)
-                                       CPU ?= athlon
+$(call                         set_if_empty,CPU,athlon)
                                        CFLAGS+=-m32 -minline-all-stringops \
                                                        -falign-loops \
                                                        -mtune=$(CPU) 
@@ -843,7 +846,7 @@ ifeq                        ($(CC_SHORTVER), 3.4)
 else
                        #if gcc 3.0+
 ifeq                   ($(CC_SHORTVER), 3.0)
-                                       CPU ?= athlon
+$(call                         set_if_empty,CPU,athlon)
                                        CFLAGS+=-minline-all-stringops \
                                                        -falign-loops \
                                                        -mcpu=$(CPU)
@@ -891,7 +894,7 @@ ifeq                ($(CC_NAME), gcc)
                                CFLAGS=-g -O9 -funroll-loops  -Wcast-align $(PROFILE)
                        #if gcc 4.2+
 ifeq                   ($(CC_SHORTVER), 4.2+)
-                                       CPU ?= opteron
+$(call                         set_if_empty,CPU,opteron)
                                        CFLAGS+=-m64 -minline-all-stringops \
                                                        -falign-loops \
                                                        -ftree-vectorize \
@@ -901,7 +904,7 @@ ifeq                        ($(CC_SHORTVER), 4.2+)
 else
                        #if gcc 4.0+
 ifeq                   ($(CC_SHORTVER), 4.x)
-                                       CPU ?= opteron
+$(call                         set_if_empty,CPU,opteron)
                                        CFLAGS+=-m64 -minline-all-stringops \
                                                        -falign-loops \
                                                        -ftree-vectorize \
@@ -910,14 +913,14 @@ ifeq                      ($(CC_SHORTVER), 4.x)
 else
                        #if gcc 3.4
 ifeq                   ($(CC_SHORTVER), 3.4)
-                                       CPU ?= athlon64
+$(call                         set_if_empty,CPU,athlon64)
                                        CFLAGS+=-m64 -minline-all-stringops \
                                                        -falign-loops 
                                        LDFLAGS+=-m64
 else
                        #if gcc 3.0
 ifeq                   ($(CC_SHORTVER), 3.0)
-                                       CPU ?= athlon64
+$(call                         set_if_empty,CPU,athlon64)
                                        CFLAGS+=-minline-all-stringops \
                                                        -falign-loops 
                                                        #-mcpu=$(CPU) \ # not working on all x86_64 gccs
@@ -968,7 +971,7 @@ ifeq                ($(CC_NAME), gcc)
                                        #-Wmissing-prototypes 
                                #if gcc 4.2+
 ifeq                   ($(CC_SHORTVER), 4.2+)
-                                       CPU ?= ultrasparc
+$(call                         set_if_empty,CPU,ultrasparc)
                                        #use 32bit for now
                                        CFLAGS+=-m64 -mcpu=ultrasparc  \
                                                        -mtune=$(CPU) \
@@ -982,7 +985,7 @@ ifeq                        ($(CC_SHORTVER), 4.2+)
 else
                                #if gcc 4.x
 ifeq                   ($(CC_SHORTVER), 4.x)
-                                       CPU ?= ultrasparc
+$(call                         set_if_empty,CPU,ultrasparc)
                                        #use 32bit for now
                                        CFLAGS+=-m64 -mcpu=ultrasparc  \
                                                        -mtune=$(CPU) \
@@ -991,14 +994,14 @@ ifeq                      ($(CC_SHORTVER), 4.x)
 else
                                #if gcc 3.4
 ifeq                   ($(CC_SHORTVER), 3.4)
-                                       CPU ?= ultrasparc
+$(call                         set_if_empty,CPU,ultrasparc)
                                        #use 32bit for now
                                        CFLAGS+=-m64 -mcpu=ultrasparc -mtune=$(CPU)
                                        LDFLAGS+=-m64
 else
                                #if gcc 3.0
 ifeq                   ($(CC_SHORTVER), 3.0)
-                                       CPU ?= ultrasparc
+$(call                         set_if_empty,CPU,ultrasparc)
                                        #use 32bit for now
                                        CFLAGS+=-m64 -mcpu=ultrasparc -mtune=$(CPU)   \
                                        # -mcpu=v9 or ultrasparc? # -mtune implied by -mcpu
@@ -1059,7 +1062,7 @@ ifeq              ($(CC_NAME), gcc)
                                        #-Wmissing-prototypes 
                                #if gcc 4.2+
 ifeq                   ($(CC_SHORTVER), 4.2+)
-                                       CPU ?= v8 
+$(call                         set_if_empty,CPU,v8)
                                        #use 32bit for now
                                        CFLAGS+= -mtune=$(CPU) \
                                                        -fno-strict-overflow \
@@ -1067,20 +1070,20 @@ ifeq                    ($(CC_SHORTVER), 4.2+)
 else
                                #if gcc 4.x
 ifeq                   ($(CC_SHORTVER), 4.x)
-                                       CPU ?= v8 
+$(call                         set_if_empty,CPU,v8)
                                        #use 32bit for now
                                        CFLAGS+= -mtune=$(CPU) \
                                                        -ftree-vectorize
 else
                                #if gcc 3.4
 ifeq                   ($(CC_SHORTVER), 3.4)
-                                       CPU ?= v8
+$(call                         set_if_empty,CPU,v8)
                                        #use 32bit for now
                                        CFLAGS+= -mtune=$(CPU)
 else
                                #if gcc 3.0
 ifeq                   ($(CC_SHORTVER), 3.0)
-                                       CPU ?= v8 
+$(call                         set_if_empty,CPU,v8)
                                        #use 32bit for now
                                        CFLAGS+= -mtune=$(CPU)   \
                                        #-mno-epilogue #try to inline function exit code
@@ -1400,14 +1403,14 @@ ifeq            ($(CC_NAME), gcc)
                                CFLAGS= -O9 -funroll-loops -fsigned-char $(PROFILE)
                        #if gcc 4.2+
 ifeq                   ($(CC_SHORTVER), 4.2+)
-                                       CPU ?= powerpc
+$(call                         set_if_empty,CPU,powerpc)
                                        CFLAGS+=-ftree-vectorize \
                                                        -fno-strict-overflow \
                                                        -mtune=$(CPU) -maltivec
 else
                        #if gcc 4.0+
 ifeq                   ($(CC_SHORTVER), 4.x)
-                                       CPU ?= powerpc
+$(call                         set_if_empty,CPU,powerpc)
                                        CFLAGS+=-ftree-vectorize \
                                                        -mtune=$(CPU) -maltivec
 else
@@ -1449,14 +1452,14 @@ ifeq            ($(CC_NAME), gcc)
                                CFLAGS= -O9 -funroll-loops -fsigned-char $(PROFILE)
                        #if gcc 4.2+
 ifeq                   ($(CC_SHORTVER), 4.2+)
-                                       CPU ?= powerpc64
+$(call                         set_if_empty,CPU,powerpc64)
                                        CFLAGS+=-ftree-vectorize \
                                                        -fno-strict-overflow \
                                                        -mtune=$(CPU) -maltivec
 else
                        #if gcc 4.0+
 ifeq                   ($(CC_SHORTVER), 4.x)
-                                       CPU ?= powerpc64
+$(call                         set_if_empty,CPU,powerpc64)
                                        CFLAGS+=-ftree-vectorize \
                                                        -mtune=$(CPU) -maltivec
 else