Makefiles: test CC prior to surcharge it

Verifies that CC is at its default value prior to try to surcharge it
with colorgcc.

libowlps-client/Makefile

@@ -1,7 +1,9 @@
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Other tools

libowlps-resultreader/Makefile

@@ -1,7 +1,9 @@
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Other tools

libowlps/Makefile

@@ -5,9 +5,11 @@ INSTALL_INC= $(PREFIX)/include
 INSTALL_MAN= $(PREFIX)/share/man
 
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Other tools

owlps-aggregator/Makefile

@@ -11,9 +11,11 @@ INSTALL_INC= $(PREFIX)/include
 INSTALL_MAN= $(PREFIX)/share/man
 
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Install/uninstall commands

owlps-client/Makefile

@@ -11,9 +11,11 @@ INSTALL_INC= $(PREFIX)/include
 INSTALL_MAN= $(PREFIX)/share/man
 
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Install/uninstall commands

owlps-listener/Makefile

@@ -11,9 +11,11 @@ INSTALL_INC= $(PREFIX)/include
 INSTALL_MAN= $(PREFIX)/share/man
 
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Install/uninstall commands

owlps-positioning/Makefile

@@ -26,9 +26,11 @@ CPPCHECK = cppcheck --quiet --enable=all
 DOXYGEN = OWLPS_VERSION=$(OWLPS_VERSION) doxygen >/dev/null
 
 # Compilation tools
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CXX = colorgcc
+ifeq "$(origin CXX)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CXX = colorgcc
+	endif
 endif
 
 # Flags

owlps-udp-to-http/Makefile

@@ -11,9 +11,11 @@ INSTALL_INC= $(PREFIX)/include
 INSTALL_MAN= $(PREFIX)/share/man
 
 # Compiler
-COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
-ifeq ($(COLORGCC), 0)
-	CC = colorgcc
+ifeq "$(origin CC)" "default"
+	COLORGCC := $(shell which colorgcc >/dev/null 2>&1 ; echo $$?)
+	ifeq "$(COLORGCC)" "0"
+		CC = colorgcc
+	endif
 endif
 
 # Install/uninstall commands