Merge pull request #260454 from aykevl/tinygo-clang-headers

tinygo: clean up Clang header path patch

pkgs/development/compilers/tinygo/0002-Add-clang-header-path.patch

···
-diff --git a/builder/builtins.go b/builder/builtins.go
-index a1066b67..f4f8ca79 100644
---- a/builder/builtins.go
-+++ b/builder/builtins.go
-@@ -179,7 +179,7 @@ var avrBuiltins = []string{
- var CompilerRT = Library{
- 	name: "compiler-rt",
- 	cflags: func(target, headerPath string) []string {
--		return []string{"-Werror", "-Wall", "-std=c11", "-nostdlibinc"}
-+		return []string{"-Werror", "-Wall", "-std=c11", "-isystem", "@clang_include@"}
- 	},
- 	sourceDir: func() string {
- 		llvmDir := filepath.Join(goenv.Get("TINYGOROOT"), "llvm-project/compiler-rt/lib/builtins")
-diff --git a/builder/picolibc.go b/builder/picolibc.go
-index 1b7c748b..8a6b9ddd 100644
---- a/builder/picolibc.go
-+++ b/builder/picolibc.go
-@@ -32,7 +32,7 @@ var Picolibc = Library{
- 			"-D__OBSOLETE_MATH_FLOAT=1", // use old math code that doesn't expect a FPU
- 			"-D__OBSOLETE_MATH_DOUBLE=0",
- 			"-D_WANT_IO_C99_FORMATS",
--			"-nostdlibinc",
-+			"-isystem", "@clang_include@",
- 			"-isystem", newlibDir + "/libc/include",
- 			"-I" + newlibDir + "/libc/tinystdio",
- 			"-I" + newlibDir + "/libm/common",
+diff --git a/builder/library.go b/builder/library.go
+index 6517355b..b8de1894 100644
+--- a/builder/library.go
++++ b/builder/library.go
+@@ -142,7 +142,7 @@ func (l *Library) load(config *compileopts.Config, tmpdir string) (job *compileJ
+ 	// Note: -fdebug-prefix-map is necessary to make the output archive
+ 	// reproducible. Otherwise the temporary directory is stored in the archive
+ 	// itself, which varies each run.
+-	args := append(l.cflags(target, headerPath), "-c", "-Oz", "-gdwarf-4", "-ffunction-sections", "-fdata-sections", "-Wno-macro-redefined", "--target="+target, "-fdebug-prefix-map="+dir+"="+remapDir)
++	args := append(l.cflags(target, headerPath), "-c", "-Oz", "-gdwarf-4", "-ffunction-sections", "-fdata-sections", "-Wno-macro-redefined", "--target="+target, "-fdebug-prefix-map="+dir+"="+remapDir, "-isystem", "@clang_include@")
+ 	cpu := config.CPU()
+ 	if cpu != "" {
+ 		// X86 has deprecated the -mcpu flag, so we need to use -march instead.
 diff --git a/compileopts/config.go b/compileopts/config.go
-index 9a4bc310..424421ae 100644
+index 39fc4f2a..8711b5a8 100644
 --- a/compileopts/config.go
 +++ b/compileopts/config.go
-@@ -276,6 +276,7 @@ func (c *Config) CFlags() []string {
- 		path, _ := c.LibcPath("picolibc")
- 		cflags = append(cflags,
- 			"--sysroot="+path,
-+			"-isystem", "@clang_include@",
- 			"-isystem", filepath.Join(path, "include"), // necessary for Xtensa
- 			"-isystem", filepath.Join(picolibcDir, "include"),
- 			"-isystem", filepath.Join(picolibcDir, "tinystdio"),
-@@ -285,7 +286,6 @@ func (c *Config) CFlags() []string {
- 		path, _ := c.LibcPath("musl")
- 		arch := MuslArchitecture(c.Triple())
- 		cflags = append(cflags,
--			"-nostdlibinc",
- 			"-isystem", filepath.Join(path, "include"),
- 			"-isystem", filepath.Join(root, "lib", "musl", "arch", arch),
- 			"-isystem", filepath.Join(root, "lib", "musl", "include"),
+@@ -264,6 +264,7 @@ func (c *Config) CFlags() []string {
+ 	for _, flag := range c.Target.CFlags {
+ 		cflags = append(cflags, strings.ReplaceAll(flag, "{root}", goenv.Get("TINYGOROOT")))
+ 	}
++	cflags = append([]string{"-isystem", "@clang_include@"}, cflags...)
+ 	switch c.Target.Libc {
+ 	case "darwin-libSystem":
+ 		root := goenv.Get("TINYGOROOT")

pkgs/development/compilers/tinygo/default.nix

···
   patches = [
     ./0001-Makefile.patch
 
+    # clang.cc does not have any paths in the include path.
+    # For TinyGo, we want to have no include paths, _except_ for the built-in
+    # Clang header files (things like stdint.h). That's why we use -nostdlibinc.
+    # So to make Clang work like we want, we will have to manually add this one
+    # include path.
+    # We can't use a regular clang command (something like
+    # llvmPackages.clangUseLLVM) because there are various bugs, see:
+    # https://github.com/NixOS/nixpkgs/issues/259397
+    # https://github.com/NixOS/nixpkgs/issues/259386
     (substituteAll {
       src = ./0002-Add-clang-header-path.patch;
       clang_include = "${clang.cc.lib}/lib/clang/${llvmMajor}/include";
···
     substituteInPlace builder/buildid.go \
       --replace "OUT_PATH" "$out"
 
-    # TODO: Fix mingw and darwin
-    # Disable windows and darwin cross-compile tests
+    # TODO: Fix mingw
+    # Disable windows cross-compile tests
     sed -i "/GOOS=windows/d" Makefile
-    sed -i "/GOOS=darwin/d" Makefile
   '' + lib.optionalString (stdenv.buildPlatform != stdenv.hostPlatform) ''
     substituteInPlace Makefile \
       --replace "./build/tinygo" "${buildPackages.tinygo}/bin/tinygo"