Re: [PATCH] Make -Werror optional

This adds new CONFIG_RTE_ERROR_ON_WARNING config option to enable
fail-on-warning compile behavior, defaulting to off.

Failing build on warnings is a useful developer tool but its bad
for release tarballs which can and do get built with newer
compilers than what was used/available during development. Compilers
routinely add new warnings so code which built silently with cc X
might no longer do so with X+1. This doesn't make the existing code
any more buggier and failing the build in this case does not help
not help improve code quality of an already released version either.
---
 config/common_bsdapp           | 1 +
 config/common_linuxapp         | 1 +
 mk/toolchain/clang/rte.vars.mk | 5 ++++-
 mk/toolchain/gcc/rte.vars.mk   | 5 ++++-
 mk/toolchain/icc/rte.vars.mk   | 6 +++++-
 5 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/config/common_bsdapp b/config/common_bsdapp
index 57bacb8..a5687b3 100644
--- a/config/common_bsdapp
+++ b/config/common_bsdapp

@@ -362,6 +362,7 @@ CONFIG_RTE_KNI_VHOST_DEBUG_TX=n
 # Enable warning directives
 #
 CONFIG_RTE_INSECURE_FUNCTION_WARNING=n
+CONFIG_RTE_ERROR_ON_WARNING=n
 
 #
 # Compile the test application

diff --git a/config/common_linuxapp b/config/common_linuxapp
index d428f84..0762f99 100644
--- a/config/common_linuxapp
+++ b/config/common_linuxapp

@@ -383,6 +383,7 @@ CONFIG_RTE_LIBRTE_XEN_DOM0=n
 # Enable warning directives
 #
 CONFIG_RTE_INSECURE_FUNCTION_WARNING=n
+CONFIG_RTE_ERROR_ON_WARNING=n
 
 #
 # Compile the test application

diff --git a/mk/toolchain/clang/rte.vars.mk b/mk/toolchain/clang/rte.vars.mk
index 40cb389..12726e7 100644
--- a/mk/toolchain/clang/rte.vars.mk
+++ b/mk/toolchain/clang/rte.vars.mk

@@ -63,11 +63,14 @@ TOOLCHAIN_ASFLAGS =
 TOOLCHAIN_CFLAGS =
 TOOLCHAIN_LDFLAGS =
 
-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 += -Wnested-externs -Wcast-qual
 WERROR_FLAGS += -Wformat-nonliteral -Wformat-security
 WERROR_FLAGS += -Wundef -Wwrite-strings
+ifeq ($(CONFIG_RTE_ERROR_ON_WARNING),y)
+WERROR_FLAGS += -Werror
+endif
 
 # process cpu flags
 include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.toolchain-compat.mk

diff --git a/mk/toolchain/gcc/rte.vars.mk b/mk/toolchain/gcc/rte.vars.mk
index 88f235c..bbd3c85 100644
--- a/mk/toolchain/gcc/rte.vars.mk
+++ b/mk/toolchain/gcc/rte.vars.mk

@@ -71,11 +71,14 @@ 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
 WERROR_FLAGS += -Wundef -Wwrite-strings
+ifeq ($(CONFIG_RTE_ERROR_ON_WARNING),y)
+WERROR_FLAGS += -Werror
+endif
 
 # process cpu flags
 include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.toolchain-compat.mk

diff --git a/mk/toolchain/icc/rte.vars.mk b/mk/toolchain/icc/rte.vars.mk
index e39d710..652cca8 100644
--- a/mk/toolchain/icc/rte.vars.mk
+++ b/mk/toolchain/icc/rte.vars.mk

@@ -69,8 +69,12 @@ TOOLCHAIN_ASFLAGS =
 #   error #13368: loop was not vectorized with "vector always assert"
 #   error #15527: loop was not vectorized: function call to fprintf cannot be vectorize
 #                   was declared "deprecated"
-WERROR_FLAGS := -Wall -Werror-all -w2 -diag-disable 271 -diag-warning 1478
+WERROR_FLAGS := -Wall -w2 -diag-disable 271 -diag-warning 1478
 WERROR_FLAGS += -diag-disable 13368 -diag-disable 15527
+ifeq ($(CONFIG_RTE_ERROR_ON_WARNING),y)
+WERROR_FLAGS += -Werror-all
+endif
+
 
 # process cpu flags
 include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.toolchain-compat.mk