mk: adjust gcc flags for new gcc 7 warnings

[dpdk.git] / mk / toolchain / gcc / rte.vars.mk

diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk
index 58faa39..3834e00 100644 (file)
--- a/mk/toolchain/gcc/rte.vars.mk
+++ b/mk/toolchain/gcc/rte.vars.mk
@@ -37,10 +37,9 @@
 #   - define TOOLCHAIN_LDFLAGS variable (overriden by cmdline value)
 #   - define TOOLCHAIN_ASFLAGS variable (overriden by cmdline value)
 #
-# examples for RTE_TOOLCHAIN: gcc, icc
-#
 
 CC        = $(CROSS)gcc
+KERNELCC  = $(CROSS)gcc
 CPP       = $(CROSS)cpp
 # for now, we don't use as but nasm.
 # AS      = $(CROSS)as
@@ -53,7 +52,11 @@ STRIP     = $(CROSS)strip
 READELF   = $(CROSS)readelf
 GCOV      = $(CROSS)gcov
 
+ifeq ("$(origin CC)", "command line")
+HOSTCC    = $(CC)
+else
 HOSTCC    = gcc
+endif
 HOSTAS    = as
 
 TOOLCHAIN_ASFLAGS =
@@ -68,18 +71,40 @@ ifeq (,$(findstring -O0,$(EXTRA_CFLAGS)))
 endif
 endif
 
-WERROR_FLAGS := -W -Wall -Werror -Wstrict-prototypes -Wmissing-prototypes
+WERROR_FLAGS := -W -Wall -Wstrict-prototypes -Wmissing-prototypes
 WERROR_FLAGS += -Wmissing-declarations -Wold-style-definition -Wpointer-arith
 WERROR_FLAGS += -Wcast-align -Wnested-externs -Wcast-qual
 WERROR_FLAGS += -Wformat-nonliteral -Wformat-security
-
-ifeq ($(CONFIG_RTE_EXEC_ENV),"linuxapp")
-# These trigger warnings in newlib, so can't be used for baremetal
 WERROR_FLAGS += -Wundef -Wwrite-strings
+
+ifeq ($(RTE_DEVEL_BUILD),y)
+WERROR_FLAGS += -Werror
+endif
+
+# There are many issues reported for strict alignment architectures
+# which are not necessarily fatal. Report as warnings.
+ifeq ($(CONFIG_RTE_ARCH_STRICT_ALIGN),y)
+WERROR_FLAGS += -Wno-error=cast-align
 endif
 
 # process cpu flags
 include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.toolchain-compat.mk
 
+# workaround GCC bug with warning "missing initializer" for "= {0}"
+ifeq ($(shell test $(GCC_VERSION) -lt 47 && echo 1), 1)
+WERROR_FLAGS += -Wno-missing-field-initializers
+endif
+# workaround GCC bug with warning "may be used uninitialized"
+ifeq ($(shell test $(GCC_VERSION) -lt 47 && echo 1), 1)
+WERROR_FLAGS += -Wno-uninitialized
+endif
+
+ifeq ($(shell test $(GCC_VERSION) -gt 70 && echo 1), 1)
+# Tell GCC only to error for switch fallthroughs without a suitable comment
+WERROR_FLAGS += -Wimplicit-fallthrough=2
+# Ignore errors for snprintf truncation
+WERROR_FLAGS += -Wno-format-truncation
+endif
+
 export CC AS AR LD OBJCOPY OBJDUMP STRIP READELF
 export TOOLCHAIN_CFLAGS TOOLCHAIN_LDFLAGS TOOLCHAIN_ASFLAGS