Add Nix support on macOS

GNUmakefile

@@ -25,21 +25,13 @@ CLANG ?= $(call findLLVMTool,clang)
 LLVM_AR ?= $(call findLLVMTool,llvm-ar)
 LLVM_NM ?= $(call findLLVMTool,llvm-nm)
 
-# Patch up Clang for Nix.
-ifneq (, ${CLANG_RESOURCE_DIR})
-    CLANG := $(CLANG) -resource-dir ${CLANG_RESOURCE_DIR}
-endif
-
 # Go binary and GOROOT to select
 GO ?= go
 export GOROOT = $(shell $(GO) env GOROOT)
 
 # Flags to pass to go test.
 GOTESTFLAGS ?=
 
-# md5sum binary
-MD5SUM = md5sum
-
 # tinygo binary for tests
 TINYGO ?= $(call detect,tinygo,tinygo $(CURDIR)/build/tinygo)
 
@@ -135,21 +127,24 @@ ifeq ($(OS),Windows_NT)
     USE_SYSTEM_BINARYEN ?= 1
 
 else ifeq ($(shell uname -s),Darwin)
-    MD5SUM = md5
+    MD5SUM ?= md5
 
     CGO_LDFLAGS += -lxar
 
     USE_SYSTEM_BINARYEN ?= 1
 
 else ifeq ($(shell uname -s),FreeBSD)
-    MD5SUM = md5
+    MD5SUM ?= md5
     START_GROUP = -Wl,--start-group
     END_GROUP = -Wl,--end-group
 else
     START_GROUP = -Wl,--start-group
     END_GROUP = -Wl,--end-group
 endif
 
+# md5sum binary default, can be overridden by an environment variable
+MD5SUM ?= md5sum
+
 # Libraries that should be linked in for the statically linked Clang.
 CLANG_LIB_NAMES = clangAnalysis clangAST clangASTMatchers clangBasic clangCodeGen clangCrossTU clangDriver clangDynamicASTMatchers clangEdit clangExtractAPI clangFormat clangFrontend clangFrontendTool clangHandleCXX clangHandleLLVM clangIndex clangLex clangParse clangRewrite clangRewriteFrontend clangSema clangSerialization clangSupport clangTooling clangToolingASTDiff clangToolingCore clangToolingInclusions
 CLANG_LIBS = $(START_GROUP) $(addprefix -l,$(CLANG_LIB_NAMES)) $(END_GROUP) -lstdc++

builder/buildid.go

@@ -77,6 +77,15 @@ func ReadBuildID() ([]byte, error) {
 			}
 			return raw[4:], nil
 		}
+
+		// Normally we would have found a build ID by now. But not on Nix,
+		// unfortunately, because Nix adds -no_uuid for some reason:
+		// https://github.com/NixOS/nixpkgs/issues/178366
+		// Fall back to the same implementation that we use for Windows.
+		id, err := readRawGoBuildID(f, 32*1024)
+		if len(id) != 0 || err != nil {
+			return id, err
+		}
 	default:
 		// On other platforms (such as Windows) there isn't such a convenient
 		// build ID. Luckily, Go does have an equivalent of the build ID, which
@@ -88,16 +97,31 @@ func ReadBuildID() ([]byte, error) {
 		// directly. Luckily the build ID is always at the start of the file.
 		// For details, see:
 		// https://github.com/golang/go/blob/master/src/cmd/internal/buildid/buildid.go
-		fileStart := make([]byte, 4096)
-		_, err := io.ReadFull(f, fileStart)
-		index := bytes.Index(fileStart, []byte("\xff Go build ID: \""))
-		if index < 0 || index > len(fileStart)-103 {
-			return nil, fmt.Errorf("could not find build id in %s", err)
-		}
-		buf := fileStart[index : index+103]
-		if bytes.HasPrefix(buf, []byte("\xff Go build ID: \"")) && bytes.HasSuffix(buf, []byte("\"\n \xff")) {
-			return buf[len("\xff Go build ID: \"") : len(buf)-1], nil
+		id, err := readRawGoBuildID(f, 4096)
+		if len(id) != 0 || err != nil {
+			return id, err
 		}
 	}
-	return nil, fmt.Errorf("could not find build ID in %s", executable)
+	return nil, fmt.Errorf("could not find build ID in %v", executable)
+}
+
+// The Go toolchain stores a build ID in the binary that we can use, as a
+// fallback if binary file specific build IDs can't be obtained.
+// This function reads that build ID from the binary.
+func readRawGoBuildID(f *os.File, prefixSize int) ([]byte, error) {
+	fileStart := make([]byte, prefixSize)
+	_, err := io.ReadFull(f, fileStart)
+	if err != nil {
+		return nil, fmt.Errorf("could not read build id from %s: %v", f.Name(), err)
+	}
+	index := bytes.Index(fileStart, []byte("\xff Go build ID: \""))
+	if index < 0 || index > len(fileStart)-103 {
+		return nil, fmt.Errorf("could not find build id in %s", f.Name())
+	}
+	buf := fileStart[index : index+103]
+	if bytes.HasPrefix(buf, []byte("\xff Go build ID: \"")) && bytes.HasSuffix(buf, []byte("\"\n \xff")) {
+		return buf[len("\xff Go build ID: \"") : len(buf)-1], nil
+	}
+
+	return nil, nil
 }

cgo/libclang_config_llvm15.go

@@ -8,8 +8,8 @@ package cgo
 #cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/llvm@15/include
 #cgo freebsd      CFLAGS:  -I/usr/local/llvm15/include
 #cgo linux        LDFLAGS: -L/usr/lib/llvm-15/lib -lclang
-#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@15/lib -lclang -lffi
-#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@15/lib -lclang -lffi
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@15/lib -lclang
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@15/lib -lclang
 #cgo freebsd      LDFLAGS: -L/usr/local/llvm15/lib -lclang
 */
 import "C"

cgo/libclang_config_llvm16.go

@@ -14,8 +14,8 @@ package cgo
 #cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/llvm@16/include
 #cgo freebsd      CFLAGS:  -I/usr/local/llvm16/include
 #cgo linux        LDFLAGS: -L/usr/lib/llvm-16/lib -lclang
-#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@16/lib -lclang -lffi
-#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@16/lib -lclang -lffi
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@16/lib -lclang
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@16/lib -lclang
 #cgo freebsd      LDFLAGS: -L/usr/local/llvm16/lib -lclang
 */
 import "C"

cgo/libclang_config_llvm17.go

@@ -8,8 +8,8 @@ package cgo
 #cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/llvm@17/include
 #cgo freebsd      CFLAGS:  -I/usr/local/llvm17/include
 #cgo linux        LDFLAGS: -L/usr/lib/llvm-17/lib -lclang
-#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@17/lib -lclang -lffi
-#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@17/lib -lclang -lffi
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@17/lib -lclang
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@17/lib -lclang
 #cgo freebsd      LDFLAGS: -L/usr/local/llvm17/lib -lclang
 */
 import "C"

flake.nix

@@ -64,10 +64,20 @@
             #openocd
           ];
           shellHook= ''
+            # Configure CLANG, LLVM_AR, and LLVM_NM for `make wasi-libc`.
+            # Without setting these explicitly, Homebrew versions might be used
+            # or the default `ar` and `nm` tools might be used (which don't
+            # support wasi).
+            export CLANG="clang-16 -resource-dir ${llvmPackages_16.clang.cc.lib}/lib/clang/16"
+            export LLVM_AR=llvm-ar
+            export LLVM_NM=llvm-nm
+
+            # Make `make smoketest` work (the default is `md5`, while Nix only
+            # has `md5sum`).
+            export MD5SUM=md5sum
+
             # Ugly hack to make the Clang resources directory available.
-            # Perhaps there is a cleaner way to do it, but this works.
-            export CLANG_RESOURCE_DIR="${llvmPackages_16.clang.cc.lib}/lib/clang/16"
-            export GOFLAGS="\"-ldflags=-X github.com/tinygo-org/tinygo/goenv.clangResourceDir=$CLANG_RESOURCE_DIR"\"
+            export GOFLAGS="\"-ldflags=-X github.com/tinygo-org/tinygo/goenv.clangResourceDir=${llvmPackages_16.clang.cc.lib}/lib/clang/16"\"
           '';
         };
       }

go.mod

@@ -18,7 +18,7 @@ require (
 	golang.org/x/sys v0.11.0
 	golang.org/x/tools v0.12.0
 	gopkg.in/yaml.v2 v2.4.0
-	tinygo.org/x/go-llvm v0.0.0-20230923132128-bba3c7009bfd
+	tinygo.org/x/go-llvm v0.0.0-20231014233752-75a8a9fe6f74
 )
 
 require (

go.sum

@@ -65,5 +65,5 @@ gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
-tinygo.org/x/go-llvm v0.0.0-20230923132128-bba3c7009bfd h1:iSVvs8r3ooxYTsmcf7FKCHq83eOSUkWKtmQhnDadDQU=
-tinygo.org/x/go-llvm v0.0.0-20230923132128-bba3c7009bfd/go.mod h1:GFbusT2VTA4I+l4j80b17KFK+6whv69Wtny5U+T8RR0=
+tinygo.org/x/go-llvm v0.0.0-20231014233752-75a8a9fe6f74 h1:tW8XhLI9gUZLL+2pG0HYb5dc6bpMj1aqtESpizXPnMY=
+tinygo.org/x/go-llvm v0.0.0-20231014233752-75a8a9fe6f74/go.mod h1:GFbusT2VTA4I+l4j80b17KFK+6whv69Wtny5U+T8RR0=