From a988124db967e03f49593393eb73b95b217cc389 Mon Sep 17 00:00:00 2001
From: Seth Howell <seth.howell@intel.com>
Date: Thu, 29 Aug 2019 09:18:37 -0700
Subject: [PATCH] make: override scan-build for unit tests.

The unit test mock macro function doesn't mesh well with the scan-build
static analysis tool. So we need to reset cc to the user provided value
or default before running the unit tests.

Change-Id: Ib636f6e396b09f9bf1cb8f930e6befa56ce99848
Signed-off-by: Seth Howell <seth.howell@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/466816
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
---
 configure            | 2 +-
 mk/spdk.unittest.mk  | 9 +++++++++
 scripts/detect_cc.sh | 1 +
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index e4ec0a160..a670ea02d 100755
--- a/configure
+++ b/configure
@@ -368,7 +368,7 @@ done
 # Detect the compiler toolchain
 $rootdir/scripts/detect_cc.sh --cc="$CC" --cxx="$CXX" --lto="${CONFIG[LTO]}" --ld="$LD" --cross-prefix="${CONFIG[CROSS_PREFIX]}"  > $rootdir/mk/cc.mk
 
-CC=$(cat $rootdir/mk/cc.mk | grep "CC=" | cut -d "=" -f 2)
+CC=$(cat $rootdir/mk/cc.mk | grep "DEFAULT_CC=" | cut -d "=" -f 2)
 CC_TYPE=$(cat $rootdir/mk/cc.mk | grep "CC_TYPE=" | cut -d "=" -f 2)
 
 BUILD_CMD=($CC -o /dev/null -x c $CPPFLAGS $CFLAGS $LDFLAGS)
diff --git a/mk/spdk.unittest.mk b/mk/spdk.unittest.mk
index 8ab55983a..91345aa55 100644
--- a/mk/spdk.unittest.mk
+++ b/mk/spdk.unittest.mk
@@ -35,6 +35,15 @@ include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 include $(SPDK_ROOT_DIR)/mk/spdk.app_vars.mk
 include $(SPDK_ROOT_DIR)/mk/spdk.mock.unittest.mk
 
+# We don't want to run scan-build against the unit tests
+# because it can't understand our mock function macros and
+# throws false positives because of them.
+
+# Scan-build inserts a phony compiler by overriding the value
+# of CC, so we store the original CC under DEFAULT_CC and
+# re-assign it here.
+override CC=$(DEFAULT_CC)
+
 C_SRCS = $(TEST_FILE)
 
 CFLAGS += -I$(SPDK_ROOT_DIR)/lib
diff --git a/scripts/detect_cc.sh b/scripts/detect_cc.sh
index 7315baaa0..b8d3e433a 100755
--- a/scripts/detect_cc.sh
+++ b/scripts/detect_cc.sh
@@ -168,6 +168,7 @@ if [ -n "$CROSS_PREFIX" ]; then
 fi
 
 function set_default() {
+	echo "DEFAULT_$1=$2"
 	echo "ifeq (\$(origin $1),default)"
 	echo "$1=$2"
 	echo "endif"