[llvmlinux] [GSoC: Static analysis] Report 1 + PATCH

[Eduard Bachmakov]

Hey everyone,

After what felt like a million do-overs I think I found a workable
location for the integration of clang-analyzer. See patch below.

The GOOD: x64 works. How?

    cd targets/x86_64; make kernel-scan-build; scan-view <watch end of
output, last line before time statistics>

The BAD: Should work for other targets, however, it seems some flags
aren't passed down in cases of cross-compilation, I'm ironing that
out. Feel free to try though!

The UGLY: takes forever. However, JSM might donate a stripped down
.config soon. That would speed things up a bit.

This code will also be pushed to my branch once I get access.

Comments, concerns? Also, despite using git imap-send, I'm afraid
gmail might screw things up. In that case please respond, I'll send
out an attachment.

---
Build a clang-analyzer target into the build-system.

Run "make kernel-build-scan"
USE ENABLE_CHECKERS/DISABLE_CHECKERS in <target>/Makefile to customize.

Tested on x64. Fails on ARM (flags not passed correctly?).

Signed-off-by: Eduard Bachmakov <e.bachmakov at gmail.com>
---
 arch/all/all.mk                | 18 +++++++++++++++++-
 arch/arm/bin/make-kernel.sh    |  5 ++++-
 arch/x86_64/bin/make-kernel.sh |  4 +++-
 targets/x86_64/Makefile        |  3 +++
 4 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/arch/all/all.mk b/arch/all/all.mk
index 8104e61..076a748 100644
--- a/arch/all/all.mk
+++ b/arch/all/all.mk
@@ -138,6 +138,16 @@ VERSION_TARGETS += ${KERNEL_TARGETS_VERSION}
 .PHONY: ${KERNEL_TARGETS_CLANG} ${KERNEL_TARGETS_GCC}
${KERNEL_TARGETS_APPLIED} ${KERNEL_TARGETS_CLEAN}
${KERNEL_TARGETS_VERSION}

 #############################################################################
+SCAN_BUILD := scan-build
+SCAN_BUILD_FLAGS := --use-cc=clang
+ifdef ENABLE_CHECKERS
+ SCAN_BUILD_FLAGS += -enable-checker ${ENABLE_CHECKERS}
+endif
+ifdef DISABLE_CHECKERS
+ SCAN_BUILD_FLAGS += -disable-checker ${DISABLE_CHECKERS}
+endif
+
+#############################################################################
 kernel-help:
  @echo
  @echo "These are the kernel make targets:"
@@ -303,7 +313,7 @@ state/kernel-build: ${TMPDIR}
${LLVMSTATE}/clang-build ${STATE_TOOLCHAIN} state/
  @[ -d ${KERNEL_BUILD} ] || ($(call
leavestate,${STATEDIR},kernel-configure) && ${MAKE} kernel-configure)
  @$(MAKE) kernel-quilt-link-patches
  @$(call banner,Building kernel with clang...)
- (cd ${KERNELDIR} && ${KERNEL_VAR} time ${MAKE_KERNEL})
+ (cd ${KERNELDIR} && ${KERNEL_VAR} time ${CHECKER} ${MAKE_KERNEL})
  @$(call banner,Successfully Built kernel with clang!)
  @mkdir -p ${TOPLOGDIR}
  @( ${CLANG} --version | head -1 ; \
@@ -328,6 +338,12 @@ state/kernel-gcc-build: ${TMPDIR} ${CROSS_GCC}
${STATE_TOOLCHAIN} state/kernel-g
  $(call state,$@,done)

 #############################################################################
+kernel-scan-build: ${TMPDIR} ${LLVMSTATE}/clang-build
${STATE_TOOLCHAIN} state/kernel-configure
+ @$(eval CHECKER := ${SCAN_BUILD} ${SCAN_BUILD_FLAGS})
+ @$(call banner,Enabling clang static analyzer: ${CHECKER})
+ ${MAKE} CHECKER="${CHECKER}" kernel-build
+
+#############################################################################
 kernel-build-force kernel-gcc-build-force: %-force:
  @rm -f state/$*
  ${MAKE} $*
diff --git a/arch/arm/bin/make-kernel.sh b/arch/arm/bin/make-kernel.sh
index fa11a2e..5d0e51b 100755
--- a/arch/arm/bin/make-kernel.sh
+++ b/arch/arm/bin/make-kernel.sh
@@ -29,7 +29,10 @@ EXTRAFLAGS=$*

 # Use clang by default
 if [ -z "$USEGCC" ]; then
- CC="clang -gcc-toolchain $COMPILER_PATH" # $CLANGFLAGS"
+ if [ -z "$CC" ]; then
+ CC="clang"
+ fi
+ CFLAGS="-gcc-toolchain $COMPILER_PATH" # $CLANGFLAGS"
 else
  CC=${CROSS_COMPILE}gcc
 fi
diff --git a/arch/x86_64/bin/make-kernel.sh b/arch/x86_64/bin/make-kernel.sh
index 8eb4074..e76bc31 100755
--- a/arch/x86_64/bin/make-kernel.sh
+++ b/arch/x86_64/bin/make-kernel.sh
@@ -29,7 +29,9 @@ EXTRAFLAGS=$*

 # Use clang by default
 if [ -z "$USEGCC" ]; then
- CC="clang"
+ if [ -z "$CC" ]; then
+ CC="clang"
+ fi
 fi

 JOBS=${JOBS:-`getconf _NPROCESSORS_ONLN`}
diff --git a/targets/x86_64/Makefile b/targets/x86_64/Makefile
index c3a66b6..db218e8 100644
--- a/targets/x86_64/Makefile
+++ b/targets/x86_64/Makefile
@@ -32,6 +32,9 @@ KERNEL_CFG = ${TARGETDIR}/config_x86_64
 #GDB_OPTS = -gdb tcp::1234 -s -S
 GDB_OPTS =

+ENABLE_CHECKERS =
+DISABLE_CHECKERS =
+
 all: prep kernel-build

 include ${TOPDIR}/common.mk
--
1.8.3.1