diff --git a/conf/Makefile.chibios-libopencm3 b/conf/Makefile.chibios-libopencm3
index d3b9ec0c82..e281206da7 100644
--- a/conf/Makefile.chibios-libopencm3
+++ b/conf/Makefile.chibios-libopencm3
@@ -283,7 +283,7 @@ DLIBS = -lm -lopencm3_stm32f4
 #
 
 # List all user C define here, like -D_DEBUG=1
-UDEFS = $($(TARGET).CFLAGS) $(LOCAL_CFLAGS) -DUSE_OCM3_SYSTICK_INIT=0
+UDEFS = $($(TARGET).CFLAGS) $(USER_CFLAGS) -DUSE_OCM3_SYSTICK_INIT=0
 
 # Define ASM defines here
 UADEFS =
diff --git a/conf/Makefile.geode b/conf/Makefile.geode
index dedaabf443..ce38405faa 100644
--- a/conf/Makefile.geode
+++ b/conf/Makefile.geode
@@ -46,7 +46,7 @@ CFLAGS += -mtune=geode # optimize for geode
 CFLAGS + = -Wstrict-prototypes -Wmissing-declarations
 CFLAGS += -Wmissing-prototypes -Wnested-externs
 CFLAGS += $(CSTANDARD)
-CFLAGS += $($(TARGET).CFLAGS) $(LOCAL_CFLAGS)
+CFLAGS += $($(TARGET).CFLAGS) $(USER_CFLAGS)
 
 #Additional libraries.
 MATH_LIB = -lm
diff --git a/conf/Makefile.jsbsim b/conf/Makefile.jsbsim
index 04044e7c27..b9dba82d4a 100644
--- a/conf/Makefile.jsbsim
+++ b/conf/Makefile.jsbsim
@@ -38,7 +38,7 @@ Q=@
 # Compilation flags
 #
 
-CFLAGS	= -W -Wall $(INCLUDES) -I$(PAPARAZZI_SRC)/sw/airborne/$(SRC_ARCH) $($(TARGET).CFLAGS) $(LOCAL_CFLAGS) -O$(OPT)
+CFLAGS	= -W -Wall $(INCLUDES) -I$(PAPARAZZI_SRC)/sw/airborne/$(SRC_ARCH) $($(TARGET).CFLAGS) $(USER_CFLAGS) -O$(OPT)
 
 LDFLAGS		=	-lm $($(TARGET).LDFLAGS)
 
diff --git a/conf/Makefile.lpc21 b/conf/Makefile.lpc21
index 473f0e06c6..117cf4607e 100644
--- a/conf/Makefile.lpc21
+++ b/conf/Makefile.lpc21
@@ -96,7 +96,7 @@ CFLAGS += -Wshadow
 CFLAGS += -Wnested-externs
 
 CFLAGS += $(CSTANDARD)
-CFLAGS += $($(TARGET).CFLAGS) $(LOCAL_CFLAGS)
+CFLAGS += $($(TARGET).CFLAGS) $(USER_CFLAGS)
 
 # Assembler flags.
 ASFLAGS = -Wa,-adhlns=$(OBJDIR)/$(notdir $(<:.S=.lst))
diff --git a/conf/Makefile.nps b/conf/Makefile.nps
index 8e1d50063d..ca309ef70a 100644
--- a/conf/Makefile.nps
+++ b/conf/Makefile.nps
@@ -35,7 +35,7 @@ Q=@
 CFLAGS  = -W -Wall
 CFLAGS += $(INCLUDES)
 CFLAGS += $($(TARGET).CFLAGS)
-CFLAGS += $(LOCAL_CFLAGS)
+CFLAGS += $(USER_CFLAGS)
 CFLAGS += -O$(OPT)
 CFLAGS += -g
 CFLAGS += -std=gnu99
@@ -44,7 +44,7 @@ CFLAGS += $(shell pkg-config --cflags-only-I ivy-glib)
 CXXFLAGS  = -W -Wall
 CXXFLAGS += $(INCLUDES)
 CXXFLAGS += $($(TARGET).CFLAGS)
-CXXFLAGS += $(LOCAL_CFLAGS)
+CXXFLAGS += $(USER_CFLAGS)
 CXXFLAGS += -O$(OPT)
 CXXFLAGS += -g
 CXXFLAGS += $(shell pkg-config --cflags-only-I ivy-glib)
diff --git a/conf/Makefile.omap b/conf/Makefile.omap
index 4e5fedcc8c..7b2e049a84 100644
--- a/conf/Makefile.omap
+++ b/conf/Makefile.omap
@@ -54,6 +54,7 @@ CFLAGS += -Wstrict-prototypes -Wmissing-declarations
 CFLAGS += -Wmissing-prototypes -Wnested-externs
 CFLAGS += $(CSTANDARD)
 CFLAGS += $($(TARGET).CFLAGS)
+CFLAGS += $(USER_CFLAGS)
 
 LDFLAGS += -lm
 
@@ -62,6 +63,7 @@ CXXFLAGS += -g -ffunction-sections -fdata-sections
 CXXFLAGS += -mfloat-abi=softfp -mtune=cortex-a8 -mfpu=vfp -march=armv7-a
 CXXFLAGS += -Wall -Wextra
 CXXFLAGS += $($(TARGET).CXXFLAGS)
+CXXFLAGS += $(USER_CFLAGS)
 
 SRC_C_OMAP  = $($(TARGET).srcs)
 OBJ_C_OMAP = $(SRC_C_OMAP:%.c=$(OBJDIR)/%.o)
diff --git a/conf/Makefile.pentium-m b/conf/Makefile.pentium-m
index 39793920df..ed9ee530d4 100644
--- a/conf/Makefile.pentium-m
+++ b/conf/Makefile.pentium-m
@@ -55,7 +55,7 @@ CFLAGS += -m32
 CFLAGS += -Wstrict-prototypes -Wmissing-declarations
 CFLAGS += -Wmissing-prototypes -Wnested-externs
 CFLAGS += $(CSTANDARD)
-CFLAGS += $($(TARGET).CFLAGS) $(LOCAL_CFLAGS)
+CFLAGS += $($(TARGET).CFLAGS) $(USER_CFLAGS)
 
 #Additional libraries.
 MATH_LIB = -lm
diff --git a/conf/Makefile.sim b/conf/Makefile.sim
index b9cf412d4f..a6dbae0e19 100644
--- a/conf/Makefile.sim
+++ b/conf/Makefile.sim
@@ -51,7 +51,7 @@ INCLUDES += -I $(shell $(OCAMLC) -where)
 CFLAGS  = -W -Wall
 CFLAGS += $(INCLUDES)
 CFLAGS += $($(TARGET).CFLAGS)
-CFLAGS += $(LOCAL_CFLAGS)
+CFLAGS += $(USER_CFLAGS)
 CFLAGS += -fPIC
 CFLAGS += -O$(OPT)
 CFLAGS += -g
diff --git a/conf/Makefile.stm32 b/conf/Makefile.stm32
index 857d31941e..44e4feb67a 100644
--- a/conf/Makefile.stm32
+++ b/conf/Makefile.stm32
@@ -102,6 +102,8 @@ CFLAGS += -Wstrict-prototypes -Wmissing-prototypes
 CFLAGS += -Wshadow
 CFLAGS += -Wnested-externs
 
+CFLAGS += $(USER_CFLAGS)
+
 #CFLAGS += -fno-diagnostics-show-caret
 
 ifneq ($(ARCH_L), )
diff --git a/tests/examples/01_compile_all_test_targets.t b/tests/examples/01_compile_all_aircrafts.t
similarity index 55%
rename from tests/examples/01_compile_all_test_targets.t
rename to tests/examples/01_compile_all_aircrafts.t
index 4fcff50f08..9c14937f01 100644
--- a/tests/examples/01_compile_all_test_targets.t
+++ b/tests/examples/01_compile_all_aircrafts.t
@@ -1,5 +1,24 @@
 #!/usr/bin/perl -w
 
+#
+# Reads conf/conf.xml (can be symlink to e.g. conf/conf_tests.xml)
+# and compiles all targets of all aircrafts.
+#
+# Mandatory environment variables:
+#  PAPARAZZI_SRC : path to paparazzi source directory
+#  PAPARAZZI_HOME : path to paparazz home directory containing the conf
+#
+# optional environment variables:
+#  TEST_VERBOSE : set to 1 to print the compile output even if there was no error
+#
+# environment variables passed on to make:
+#  J=AUTO : detect number of CPUs to set jobs for parallel compilation
+#
+# Example on how to test compile all aircrafts/targets in your current conf.xml
+# with parallel compilation and treating all warnings as errors:
+#  J=AUTO USER_CFLAGS=-Werror prove tests/examples
+#
+
 use Test::More;
 use lib "$ENV{'PAPARAZZI_SRC'}/tests/lib";
 use XML::Simple;
@@ -9,28 +28,28 @@ use Config;
 
 $|++;
 my $xmlSimple = XML::Simple->new(ForceArray => 1);
-my $examples = $xmlSimple->XMLin("$ENV{'PAPARAZZI_SRC'}/conf/conf.xml");
+my $conf = $xmlSimple->XMLin("$ENV{'PAPARAZZI_HOME'}/conf/conf.xml");
 
-ok(1, "Parsed the tests configuration file");
-foreach my $example (sort keys%{$examples->{'aircraft'}})
+ok(1, "Parsed the configuration file");
+foreach my $aircraft (sort keys%{$conf->{'aircraft'}})
 {
-	my $airframe = $examples->{'aircraft'}->{$example}->{'airframe'};
-	my $airframe_config = $xmlSimple->XMLin("$ENV{'PAPARAZZI_SRC'}/conf/$airframe");
+	my $airframe = $conf->{'aircraft'}->{$aircraft}->{'airframe'};
+	my $airframe_config = $xmlSimple->XMLin("$ENV{'PAPARAZZI_HOME'}/conf/$airframe");
 	foreach my $process (sort keys %{$airframe_config->{'firmware'}})
 	{
-        #warn "EX: [$example] ". Dumper($airframe_config->{'firmware'}->{$process}->{'target'});
+        #warn "EX: [$aircraft] ". Dumper($airframe_config->{'firmware'}->{$process}->{'target'});
         foreach my $target (sort keys %{$airframe_config->{'firmware'}->{$process}->{'target'}})
         {
-            #warn "EXAMPLE: [$example] TARGET: [$target]\n";
-            my $make_options = "AIRCRAFT=$example clean_ac $target.compile";
+            #warn "AIRCRAFT: [$aircraft] TARGET: [$target]\n";
+            my $make_options = "AIRCRAFT=$aircraft clean_ac $target.compile";
             my ($exit_status, $output) = run_program(
-                "Attempting to build the firmware $target for the aircraft $example.",
+                "Attempting to build the firmware $target for the aircraft $aircraft.",
                 $ENV{'PAPARAZZI_SRC'},
                 "make $make_options",
                 $ENV{'TEST_VERBOSE'},1);
             # print output if it failed and we didn't already print it in verbose mode
             warn "$output\n" if $exit_status && !$ENV{'TEST_VERBOSE'};
-            ok($exit_status == 0, "Compile aircraft: $example, target: $target");
+            ok($exit_status == 0, "Compile aircraft: $aircraft, target: $target");
         }
 	}
 }
@@ -68,13 +87,14 @@ sub run_program
         my $exit_status = $?/256;
         unless ($exit_status == 0)
         {
+                my $err_msg = "\nError: The command \"". $prog->last_command() ."\" failed to complete successfully. Exit status: $exit_status\n";
                 if ($dont_fail_on_error)
                 {
-                        warn "\nError: The command \"". $prog->last_command() ."\" failed to complete successfully. Exit status: $exit_status\n";
+                        warn $err_msg;
                 }
                 else
                 {
-                        die "\nError: The command \"". $prog->last_command() ."\" failed to complete successfully. Exit status: $exit_status\n";
+                        die $err_msg;
                 }
         }
         my $output_string = join "\n", @output;