make: strip symbol tables from all binaries by default

Strip the symbol tables and debug information from all binaries by
default. This will not remove annotations needed for stack traces, so
panic backtraces will still be readable.

If debug information and symbol tables are needed during debugging, use
`make NOSTRIP=1` to compile.

This reduces the binary sizes (and thus the base memory consumption) as
follows:

before:

    -rwxr-xr-x 1 tklauser tklauser 46M Feb 21 14:05 cilium/cilium
    -rwxr-xr-x 1 tklauser tklauser 21M Feb 21 14:05 cilium-health/cilium-health
    -rwxr-xr-x 1 tklauser tklauser 71M Feb 21 14:05 daemon/cilium-agent
    -rwxr-xr-x 1 tklauser tklauser 74M Feb 21 14:05 operator/cilium-operator
    -rwxr-xr-x 1 tklauser tklauser 46M Feb 21 14:04 plugins/cilium-cni/cilium-cni

after:

    -rwxr-xr-x 1 tklauser tklauser 46M Feb 21 14:08 cilium/cilium
    -rwxr-xr-x 1 tklauser tklauser 15M Feb 21 14:08 cilium-health/cilium-health
    -rwxr-xr-x 1 tklauser tklauser 52M Feb 21 14:08 daemon/cilium-agent
    -rwxr-xr-x 1 tklauser tklauser 55M Feb 21 14:08 operator/cilium-operator
    -rwxr-xr-x 1 tklauser tklauser 34M Feb 21 14:08 plugins/cilium-cni/cilium-cni

summary:

    cilium           0MB (already stripped previously, see 8596bd9)
    cilium-agent    ~19MB
    cilium-health   ~6MB
    cilium-operator ~19MB
    cilium-cni      ~12MB

Also see https://blog.filippo.io/shrink-your-go-binaries-with-this-one-weird-trick/

Updates #6099
Updates #10056

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

Makefile.defs

@@ -33,6 +33,15 @@ endif
 BUILD = $(VERSION) $(GIT_VERSION) $(shell $(GO) version)
 GOLDFLAGS = -X "github.com/cilium/cilium/pkg/version.Version=$(BUILD)"
 
+ifeq ($(NOSTRIP),)
+	# Note: these options will not remove annotations needed for stack
+	# traces, so panic backtraces will still be readable.
+	#
+	# -w: Omit the DWARF symbol table.
+	# -s: Omit the symbol table and debug information.
+	GOLDFLAGS += -s -w
+endif
+
 CILIUM_ENVOY_SHA=$(shell grep -o "FROM.*cilium/cilium-envoy:[0-9a-fA-F]*" $(ROOT_DIR)/Dockerfile | cut -d : -f 2)
 GOLDFLAGS += -X "github.com/cilium/cilium/pkg/envoy.RequiredEnvoyVersionSHA=$(CILIUM_ENVOY_SHA)"
 

cilium-docker-plugin.Dockerfile

@@ -5,7 +5,6 @@ WORKDIR /go/src/github.com/cilium/cilium/plugins/cilium-docker
 ARG LOCKDEBUG
 ARG V
 RUN make CGO_ENABLED=0 GOOS=linux LOCKDEBUG=$LOCKDEBUG PKG_BUILD=1 EXTRA_GOBUILD_FLAGS="-a -installsuffix cgo"
-RUN strip cilium-docker
 
 FROM scratch
 LABEL maintainer="maintainer@cilium.io"

cilium-operator.Dockerfile

@@ -5,7 +5,6 @@ WORKDIR /go/src/github.com/cilium/cilium/operator
 ARG LOCKDEBUG
 ARG V
 RUN make CGO_ENABLED=0 GOOS=linux LOCKDEBUG=$LOCKDEBUG PKG_BUILD=1 EXTRA_GOBUILD_FLAGS="-a -installsuffix cgo"
-RUN strip cilium-operator
 
 FROM docker.io/library/alpine:3.9.3 as certs
 RUN apk --update add ca-certificates

cilium/Makefile

@@ -7,7 +7,6 @@ SOURCES := $(shell find ../api ../daemon ../common ../pkg cmd . \( -name '*.go'
 $(TARGET): $(SOURCES)
 	@$(ECHO_GO)
 	$(QUIET)$(GO) build $(GOBUILD) -o $(TARGET)
-	strip $(TARGET)
 
 all: $(TARGET)