crypto/secp256k1: remove dependency on libgmp

Turns out we actually don't need it, USE_NUM_NONE works
because we also set USE_FIELD_INV_BUILTIN.

.travis.yml

@@ -20,10 +20,6 @@ env:
   global:
     - secure: "U2U1AmkU4NJBgKR/uUAebQY87cNL0+1JHjnLOmmXwxYYyj5ralWb1aSuSH3qSXiT93qLBmtaUkuv9fberHVqrbAeVlztVdUsKAq7JMQH+M99iFkC9UiRMqHmtjWJ0ok4COD1sRYixxi21wb/JrMe3M1iL4QJVS61iltjHhVdM64="
 sudo: false
-addons:
-  apt:
-    packages:
-    - libgmp3-dev
 notifications:
   webhooks:
     urls:

Makefile

@@ -12,7 +12,6 @@
 
 GOBIN = build/bin
 
-CROSSDEPS = https://gmplib.org/download/gmp/gmp-6.1.0.tar.bz2
 MODE ?= default
 GO ?= latest
 
@@ -30,12 +29,12 @@ geth-linux: geth-linux-386 geth-linux-amd64 geth-linux-arm
 	@ls -l $(GOBIN)/geth-linux-*
 
 geth-linux-386: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=linux/386 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=linux/386 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Linux 386 cross compilation done:"
 	@ls -l $(GOBIN)/geth-linux-* | grep 386
 
 geth-linux-amd64: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=linux/amd64 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=linux/amd64 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Linux amd64 cross compilation done:"
 	@ls -l $(GOBIN)/geth-linux-* | grep amd64
 
@@ -44,22 +43,22 @@ geth-linux-arm: geth-linux-arm-5 geth-linux-arm-6 geth-linux-arm-7 geth-linux-ar
 	@ls -l $(GOBIN)/geth-linux-* | grep arm
 
 geth-linux-arm-5: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=linux/arm-5 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=linux/arm-5 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Linux ARMv5 cross compilation done:"
 	@ls -l $(GOBIN)/geth-linux-* | grep arm-5
 
 geth-linux-arm-6: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=linux/arm-6 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=linux/arm-6 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Linux ARMv6 cross compilation done:"
 	@ls -l $(GOBIN)/geth-linux-* | grep arm-6
 
 geth-linux-arm-7: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=linux/arm-7 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=linux/arm-7 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Linux ARMv7 cross compilation done:"
 	@ls -l $(GOBIN)/geth-linux-* | grep arm-7
 
 geth-linux-arm64: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=linux/arm64 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=linux/arm64 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Linux ARM64 cross compilation done:"
 	@ls -l $(GOBIN)/geth-linux-* | grep arm64
 
@@ -68,12 +67,12 @@ geth-darwin: geth-darwin-386 geth-darwin-amd64
 	@ls -l $(GOBIN)/geth-darwin-*
 
 geth-darwin-386: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=darwin/386 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=darwin/386 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Darwin 386 cross compilation done:"
 	@ls -l $(GOBIN)/geth-darwin-* | grep 386
 
 geth-darwin-amd64: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=darwin/amd64 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=darwin/amd64 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Darwin amd64 cross compilation done:"
 	@ls -l $(GOBIN)/geth-darwin-* | grep amd64
 
@@ -82,17 +81,17 @@ geth-windows: geth-windows-386 geth-windows-amd64
 	@ls -l $(GOBIN)/geth-windows-*
 
 geth-windows-386: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=windows/386 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=windows/386 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Windows 386 cross compilation done:"
 	@ls -l $(GOBIN)/geth-windows-* | grep 386
 
 geth-windows-amd64: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=windows/amd64 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=windows/amd64 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Windows amd64 cross compilation done:"
 	@ls -l $(GOBIN)/geth-windows-* | grep amd64
 
 geth-android: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --targets=android/* -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=android/* -v $(shell build/flags.sh) ./cmd/geth
 	@echo "Android cross compilation done:"
 	@ls -l $(GOBIN)/geth-android-*
 
@@ -101,12 +100,12 @@ geth-ios: geth-ios-arm-7 geth-ios-arm64
 	@ls -l $(GOBIN)/geth-ios-*
 
 geth-ios-arm-7: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --depsargs=--disable-assembly --targets=ios/arm-7 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=ios/arm-7 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "iOS ARMv7 cross compilation done:"
 	@ls -l $(GOBIN)/geth-ios-* | grep arm-7
 
 geth-ios-arm64: xgo
-	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --deps=$(CROSSDEPS) --depsargs=--disable-assembly --targets=ios-7.0/arm64 -v $(shell build/flags.sh) ./cmd/geth
+	build/env.sh $(GOBIN)/xgo --go=$(GO) --buildmode=$(MODE) --dest=$(GOBIN) --targets=ios-7.0/arm64 -v $(shell build/flags.sh) ./cmd/geth
 	@echo "iOS ARM64 cross compilation done:"
 	@ls -l $(GOBIN)/geth-ios-* | grep arm64
 

README.md

@@ -30,7 +30,7 @@ For prerequisites and detailed build instructions please read the
 [Installation Instructions](https://github.com/ethereum/go-ethereum/wiki/Building-Ethereum)
 on the wiki.
 
-Building geth requires two external dependencies, Go and GMP.
+Building geth requires both a Go and a C compiler.
 You can install them using your favourite package manager.
 Once the dependencies are installed, run
 

crypto/secp256k1/README.md

@@ -1,25 +0,0 @@
-secp256k1-go
-=======
-
-golang secp256k1 library
-
-Implements cryptographic operations for the secp256k1 ECDSA curve used by Bitcoin.
-
-Installing
-===
-
-GMP library headers are required to build. On Debian-based systems, the package is called `libgmp-dev`.
-
-```
-sudo apt-get install libgmp-dev
-```
-
-Now compiles with cgo!
-
-Test
-===
-
-To run tests do
-```
-go tests
-```

crypto/secp256k1/secp256.go

@@ -21,14 +21,7 @@ package secp256k1
 /*
 #cgo CFLAGS: -I./libsecp256k1
 #cgo CFLAGS: -I./libsecp256k1/src/
-#cgo darwin CFLAGS: -I/usr/local/include
-#cgo freebsd CFLAGS: -I/usr/local/include
-#cgo linux,arm CFLAGS: -I/usr/local/arm/include
-#cgo LDFLAGS: -lgmp
-#cgo darwin LDFLAGS: -L/usr/local/lib
-#cgo freebsd LDFLAGS: -L/usr/local/lib
-#cgo linux,arm LDFLAGS: -L/usr/local/arm/lib
-#define USE_NUM_GMP
+#define USE_NUM_NONE
 #define USE_FIELD_10X26
 #define USE_FIELD_INV_BUILTIN
 #define USE_SCALAR_8X32