feat: add libc

internal/crosscompile/crosscompile.go

@@ -8,8 +8,11 @@ import (
 	"os/exec"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"strings"
 
+	"github.com/goplus/llgo/internal/clang"
+
 	"github.com/goplus/llgo/internal/env"
 	"github.com/goplus/llgo/internal/targets"
 	"github.com/goplus/llgo/internal/xtool/llvm"
@@ -215,6 +218,70 @@ func getESPClangPlatform(goos, goarch string) string {
 	return ""
 }
 
+func getOrCompileLibc(cc, linkerName, libcName string, ccflags, exportLdFlags []string) (ldflags []string, err error) {
+	baseDir := filepath.Join(cacheRoot(), "crosscompile")
+	libcDir := filepath.Join(baseDir, libcName)
+	libcArchive := filepath.Join(libcDir, "libc.a")
+	// fast-path: compiled already
+	if _, err = os.Stat(libcArchive); !os.IsNotExist(err) {
+		ldflags = append(ldflags, "-nostdlib", "-L", libcDir, "-lc")
+		return ldflags, nil
+	}
+	compileConfig, err := getCompileLibcConfigByName(baseDir, libcName)
+	if err != nil {
+		return
+	}
+	tempDir, err := os.MkdirTemp("", "compile*")
+	if err != nil {
+		return
+	}
+	defer os.RemoveAll(tempDir)
+
+	fmt.Fprintf(os.Stderr, "%s not found in LLGO_ROOT or cache, will download and compile.\n", libcDir)
+	if err = checkDownloadAndExtractLibc(compileConfig.Url, libcDir, compileConfig.ArchiveSrcDir); err != nil {
+		return
+	}
+	compileLDFlags := append(slices.Clone(exportLdFlags), compileConfig.LDFlags...)
+
+	cfg := clang.NewConfig(cc, ccflags, compileConfig.CFlags, compileLDFlags, linkerName)
+
+	var objFiles []string
+
+	compiler := clang.NewCompiler(cfg)
+	linker := clang.NewLinker(cfg)
+
+	compiler.Verbose = true
+	linker.Verbose = true
+	fmt.Fprintf(os.Stderr, "Start to compile libc %s to %s...\n", libcName, libcArchive)
+
+	for _, file := range compileConfig.Files {
+		var tempObjFile *os.File
+		tempObjFile, err = os.CreateTemp(tempDir, "libc*.o")
+		if err != nil {
+			return
+		}
+		fmt.Fprintf(os.Stderr, "Compile libc file %s to %s...\n", file, tempObjFile.Name())
+
+		err = compiler.Compile("-o", tempObjFile.Name(), "-x", "c", "-c", file)
+		if err != nil {
+			return
+		}
+
+		objFiles = append(objFiles, tempObjFile.Name())
+	}
+
+	args := []string{"-o", libcArchive}
+	args = append(args, objFiles...)
+
+	err = linker.Link(args...)
+	if err != nil {
+		return
+	}
+	ldflags = append(ldflags, "-nostdlib", "-L", libcDir, "-lc")
+
+	return
+}
+
 func use(goos, goarch string, wasiThreads bool) (export Export, err error) {
 	targetTriple := llvm.GetTargetTriple(goos, goarch)
 	llgoRoot := env.LLGoROOT()
@@ -574,6 +641,15 @@ func useTarget(targetName string) (export Export, err error) {
 	}
 	ldflags = append(ldflags, "-L", env.LLGoROOT()) // search targets/*.ld
 
+	if config.Libc != "" {
+		var libcLDFlags []string
+		libcLDFlags, err = getOrCompileLibc(export.CC, export.Linker, config.Libc, ccflags, ldflags)
+		if err != nil {
+			return
+		}
+		ldflags = append(ldflags, libcLDFlags...)
+	}
+
 	// Combine with config flags and expand template variables
 	export.CFLAGS = cflags
 	export.CCFLAGS = ccflags

internal/crosscompile/fetch.go

@@ -8,6 +8,7 @@ import (
 	"net/http"
 	"os"
 	"os/exec"
+	"path"
 	"path/filepath"
 	"strings"
 	"syscall"
@@ -78,6 +79,47 @@ func checkDownloadAndExtractESPClang(platformSuffix, dir string) error {
 	return nil
 }
 
+func checkDownloadAndExtractLibc(url, dstDir, internalArchiveSrcDir string) error {
+	// Check if already exists
+	if _, err := os.Stat(dstDir); err == nil {
+		return nil
+	}
+
+	// Create lock file path for the final destination
+	lockPath := dstDir + ".lock"
+	lockFile, err := acquireLock(lockPath)
+	if err != nil {
+		return fmt.Errorf("failed to acquire lock: %w", err)
+	}
+	defer releaseLock(lockFile)
+
+	// Double-check after acquiring lock
+	if _, err := os.Stat(dstDir); err == nil {
+		return nil
+	}
+
+	description := fmt.Sprintf("Libc %s", path.Base(url))
+
+	// Use temporary extraction directory
+	tempExtractDir := dstDir + ".extract"
+	if err := downloadAndExtractArchive(url, tempExtractDir, description); err != nil {
+		return err
+	}
+	defer os.RemoveAll(tempExtractDir)
+
+	srcDir := tempExtractDir
+
+	if internalArchiveSrcDir != "" {
+		srcDir = filepath.Join(tempExtractDir, internalArchiveSrcDir)
+	}
+
+	if err := os.Rename(srcDir, dstDir); err != nil {
+		return fmt.Errorf("failed to rename libc directory: %w", err)
+	}
+
+	return nil
+}
+
 // acquireLock creates and locks a file to prevent concurrent operations
 func acquireLock(lockPath string) (*os.File, error) {
 	// Ensure the parent directory exists

internal/crosscompile/libc.go

@@ -0,0 +1,185 @@
+package crosscompile
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// CompileLibcConfig represents libc compilation configuration
+type compileLibcConfig struct {
+	Url           string
+	Name          string   // Libc name (e.g., "picolibc", "musl", "glibc")
+	Files         []string // List of source files to compile
+	CFlags        []string // C compiler flags specific to this libc
+	LDFlags       []string // Linker flags
+	ArchiveSrcDir string
+}
+
+// GetCompileLibcConfigByName retrieves libc compilation configuration by name
+// Returns compilation file lists and corresponding cflags
+func getCompileLibcConfigByName(baseDir, libcName string) (*compileLibcConfig, error) {
+	if libcName == "" {
+		return nil, fmt.Errorf("libc name cannot be empty")
+	}
+	libcDir := filepath.Join(baseDir, libcName)
+
+	switch libcName {
+	case "picolibc":
+		return getPicolibcConfig(libcDir), nil
+	default:
+		return nil, fmt.Errorf("unsupported libc: %s", libcName)
+	}
+}
+
+// getPicolibcConfig returns configuration for picolibc
+func getPicolibcConfig(baseDir string) *compileLibcConfig {
+	libcIncludeDir := filepath.Join(baseDir, "libc", "include")
+	libmIncludeDir := filepath.Join(baseDir, "libm", "common")
+	localeIncludeDir := filepath.Join(baseDir, "libc", "locale")
+
+	os.MkdirAll(baseDir, 0700)
+
+	headerFile, _ := os.Create(filepath.Join(baseDir, "picolibc.h"))
+	headerFile.Close()
+
+	return &compileLibcConfig{
+		Url:  "https://github.com/picolibc/picolibc/releases/download/1.8.10/picolibc-1.8.10.tar.xz",
+		Name: "picolibc",
+		Files: []string{
+			filepath.Join(baseDir, "libc", "string", "bcmp.c"),
+			filepath.Join(baseDir, "libc", "string", "bcopy.c"),
+			filepath.Join(baseDir, "libc", "string", "bzero.c"),
+			filepath.Join(baseDir, "libc", "string", "explicit_bzero.c"),
+			filepath.Join(baseDir, "libc", "string", "ffsl.c"),
+			filepath.Join(baseDir, "libc", "string", "ffsll.c"),
+			filepath.Join(baseDir, "libc", "string", "fls.c"),
+			filepath.Join(baseDir, "libc", "string", "flsl.c"),
+			filepath.Join(baseDir, "libc", "string", "flsll.c"),
+			filepath.Join(baseDir, "libc", "string", "gnu_basename.c"),
+			filepath.Join(baseDir, "libc", "string", "index.c"),
+			filepath.Join(baseDir, "libc", "string", "memccpy.c"),
+			filepath.Join(baseDir, "libc", "string", "memchr.c"),
+			filepath.Join(baseDir, "libc", "string", "memcmp.c"),
+			filepath.Join(baseDir, "libc", "string", "memcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "memmem.c"),
+			filepath.Join(baseDir, "libc", "string", "memmove.c"),
+			filepath.Join(baseDir, "libc", "string", "mempcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "memrchr.c"),
+			filepath.Join(baseDir, "libc", "string", "memset.c"),
+			filepath.Join(baseDir, "libc", "string", "rawmemchr.c"),
+			filepath.Join(baseDir, "libc", "string", "rindex.c"),
+			filepath.Join(baseDir, "libc", "string", "stpcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "stpncpy.c"),
+			filepath.Join(baseDir, "libc", "string", "strcasecmp.c"),
+			filepath.Join(baseDir, "libc", "string", "strcasecmp_l.c"),
+			filepath.Join(baseDir, "libc", "string", "strcasestr.c"),
+			filepath.Join(baseDir, "libc", "string", "strcat.c"),
+			filepath.Join(baseDir, "libc", "string", "strchr.c"),
+			filepath.Join(baseDir, "libc", "string", "strchrnul.c"),
+			filepath.Join(baseDir, "libc", "string", "strcmp.c"),
+			filepath.Join(baseDir, "libc", "string", "strcoll.c"),
+			filepath.Join(baseDir, "libc", "string", "strcoll_l.c"),
+			filepath.Join(baseDir, "libc", "string", "strcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "strcspn.c"),
+			filepath.Join(baseDir, "libc", "string", "strerror_r.c"),
+			filepath.Join(baseDir, "libc", "string", "strlcat.c"),
+			filepath.Join(baseDir, "libc", "string", "strlcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "strlen.c"),
+			filepath.Join(baseDir, "libc", "string", "strlwr.c"),
+			filepath.Join(baseDir, "libc", "string", "strncasecmp.c"),
+			filepath.Join(baseDir, "libc", "string", "strncasecmp_l.c"),
+			filepath.Join(baseDir, "libc", "string", "strncat.c"),
+			filepath.Join(baseDir, "libc", "string", "strncmp.c"),
+			filepath.Join(baseDir, "libc", "string", "strncpy.c"),
+			filepath.Join(baseDir, "libc", "string", "strndup.c"),
+			filepath.Join(baseDir, "libc", "string", "strnlen.c"),
+			filepath.Join(baseDir, "libc", "string", "strnstr.c"),
+			filepath.Join(baseDir, "libc", "string", "strpbrk.c"),
+			filepath.Join(baseDir, "libc", "string", "strrchr.c"),
+			filepath.Join(baseDir, "libc", "string", "strsep.c"),
+			filepath.Join(baseDir, "libc", "string", "strsignal.c"),
+			filepath.Join(baseDir, "libc", "string", "strspn.c"),
+			filepath.Join(baseDir, "libc", "string", "strstr.c"),
+			filepath.Join(baseDir, "libc", "string", "strtok.c"),
+			filepath.Join(baseDir, "libc", "string", "strtok_r.c"),
+			filepath.Join(baseDir, "libc", "string", "strupr.c"),
+			filepath.Join(baseDir, "libc", "string", "strverscmp.c"),
+			filepath.Join(baseDir, "libc", "string", "strxfrm.c"),
+			filepath.Join(baseDir, "libc", "string", "strxfrm_l.c"),
+			filepath.Join(baseDir, "libc", "string", "swab.c"),
+			filepath.Join(baseDir, "libc", "string", "timingsafe_bcmp.c"),
+			filepath.Join(baseDir, "libc", "string", "timingsafe_memcmp.c"),
+			filepath.Join(baseDir, "libc", "string", "strerror.c"),
+			filepath.Join(baseDir, "libc", "string", "wcpcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wcpncpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscasecmp.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscasecmp_l.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscat.c"),
+			filepath.Join(baseDir, "libc", "string", "wcschr.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscmp.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscoll.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscoll_l.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wcscspn.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsdup.c"),
+			filepath.Join(baseDir, "libc", "string", "wcslcat.c"),
+			filepath.Join(baseDir, "libc", "string", "wcslcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wcslen.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsncasecmp.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsncasecmp_l.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsncat.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsncmp.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsncpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsnlen.c"),
+			filepath.Join(baseDir, "libc", "string", "wcspbrk.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsrchr.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsspn.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsstr.c"),
+			filepath.Join(baseDir, "libc", "string", "wcstok.c"),
+			filepath.Join(baseDir, "libc", "string", "wcswidth.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsxfrm.c"),
+			filepath.Join(baseDir, "libc", "string", "wcsxfrm_l.c"),
+			filepath.Join(baseDir, "libc", "string", "wcwidth.c"),
+			filepath.Join(baseDir, "libc", "string", "wmemchr.c"),
+			filepath.Join(baseDir, "libc", "string", "wmemcmp.c"),
+			filepath.Join(baseDir, "libc", "string", "wmemcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wmemmove.c"),
+			filepath.Join(baseDir, "libc", "string", "wmempcpy.c"),
+			filepath.Join(baseDir, "libc", "string", "wmemset.c"),
+			filepath.Join(baseDir, "libc", "string", "xpg_strerror_r.c"),
+
+			filepath.Join(baseDir, "libc", "stdlib", "nano-calloc.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "nano-malloc.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "nano-pvalloc.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "nano-realloc.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "nano-valloc.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "rand.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "srand.c"),
+			filepath.Join(baseDir, "libc", "stdlib", "nano-free.c"),
+
+			filepath.Join(baseDir, "libc", "tinystdio", "printf.c"),
+			filepath.Join(baseDir, "libc", "tinystdio", "putchar.c"),
+			filepath.Join(baseDir, "libc", "tinystdio", "puts.c"),
+		},
+		CFlags: []string{
+			"-D_COMPILING_NEWLIB",
+			"-D_HAVE_ALIAS_ATTRIBUTE",
+			"-DTINY_STDIO",
+			"-DPOSIX_IO",
+			"-DFORMAT_DEFAULT_INTEGER",
+			"-D_IEEE_LIBM",
+			"-D__OBSOLETE_MATH_FLOAT=1",
+			"-D__OBSOLETE_MATH_DOUBLE=0",
+			"-D_WANT_IO_C99_FORMATS",
+			"-nostdlib",
+			"-isystem" + libcIncludeDir,
+			"-I" + libmIncludeDir,
+			"-I" + localeIncludeDir,
+			"-I" + baseDir,
+			"-I" + filepath.Join(baseDir, "libc", "tinystdio"),
+		},
+		LDFlags:       []string{"-nostdlib"},
+		ArchiveSrcDir: filepath.Join("picolibc-1.8.10", "newlib"),
+	}
+}

internal/targets/config.go

@@ -16,6 +16,7 @@ type Config struct {
 	GOARCH    string   `json:"goarch"`
 
 	// Compiler and linker configuration
+	Libc         string   `json:"libc"`
 	Linker       string   `json:"linker"`
 	LinkerScript string   `json:"linkerscript"`
 	CFlags       []string `json:"cflags"`

internal/targets/loader.go

@@ -134,6 +134,9 @@ func (l *Loader) mergeConfig(dst, src *Config) {
 	if src.GOARCH != "" {
 		dst.GOARCH = src.GOARCH
 	}
+	if src.Libc != "" {
+		dst.Libc = src.Libc
+	}
 	if src.Linker != "" {
 		dst.Linker = src.Linker
 	}

targets/esp32.ld

@@ -97,14 +97,6 @@ _heap_end = ORIGIN(DRAM) + LENGTH(DRAM);
 
 _stack_size = 4K;
 
-/* From ESP-IDF:
- * components/esp_rom/esp32/ld/esp32.rom.newlib-funcs.ld
- * This is the subset that is sometimes used by LLVM during codegen, and thus
- * must always be present.
- */
-memcpy  = 0x4000c2c8;
-memmove = 0x4000c3c0;
-memset  = 0x4000c44c;
 
 /* From ESP-IDF:
  * components/esp_rom/esp32/ld/esp32.rom.libgcc.ld
@@ -200,3 +192,9 @@ __umodsi3      = 0x4000c7d0;
 __umulsidi3    = 0x4000c7d8;
 __unorddf2     = 0x400637f4;
 __unordsf2     = 0x40063478;
+
+INCLUDE "targets/esp32.rom.newlib-data.ld";
+INCLUDE "targets/esp32.rom.newlib-funcs.ld";
+INCLUDE "targets/esp32.rom.newlib-locale.ld";
+INCLUDE "targets/esp32.rom.newlib-nano.ld";
+INCLUDE "targets/esp32.rom.newlib-time.ld";

targets/esp32.rom.newlib-data.ld

@@ -0,0 +1,23 @@
+/* These are the .bss/.data symbols used by newlib functions present in ESP32 ROM.
+   See also esp32.rom.newlib-funcs.ld for the list of general newlib functions,
+   and esp32.rom.newlib-nano.ld for "nano" versions of printf/scanf family of functions.
+
+   Unlike other ROM functions and data which are exported using PROVIDE, which declares
+   weak symbols, newlib related functions are exported using assignment,
+   which declares strong symbols. This is done so that ROM functions are always
+   used instead of the ones provided by libc.a.
+ */
+
+_ctype_ = 0x3ff96354;
+__ctype_ptr__ = 0x3ff96350;
+environ = 0x3ffae0b4;
+_global_impure_ptr = 0x3ffae0b0;
+__mb_cur_max = 0x3ff96530;
+__sf_fake_stderr = 0x3ff96458;
+__sf_fake_stdin = 0x3ff96498;
+__sf_fake_stdout = 0x3ff96478;
+__wctomb = 0x3ff96540;
+__sfp_lock = 0x3ffae0ac;
+__sinit_lock = 0x3ffae0a8;
+__env_lock_object = 0x3ffae0b8;
+__tz_lock_object = 0x3ffae080;

targets/esp32.rom.newlib-funcs.ld

@@ -0,0 +1,130 @@
+/* These are the newlib functions present in ESP32 ROM.
+   They should not be used when compiling with PSRAM cache workaround enabled.
+   See also esp32.rom.newlib-data.ld for the list of .data/.bss symbols
+   used by these functions, and esp32.rom.newlib-nano.ld for "nano" versions
+   of printf/scanf family of functions.
+
+   Unlike other ROM functions which are exported using PROVIDE, which declares
+   weak symbols, newlib related functions are exported using assignment,
+   which declares strong symbols. This is done so that ROM functions are always
+   used instead of the ones provided by libc.a.
+
+   Time functions were moved to the esp32.rom.newlib-time.ld file.
+ */
+
+abs = 0x40056340;
+__ascii_wctomb = 0x40058ef0;
+atoi = 0x400566c4;
+_atoi_r = 0x400566d4;
+atol = 0x400566ec;
+_atol_r = 0x400566fc;
+bzero = 0x4000c1f4;
+_cleanup = 0x40001df8;
+_cleanup_r = 0x40001d48;
+creat = 0x40000e8c;
+div = 0x40056348;
+__dummy_lock = 0x4000c728;
+__dummy_lock_try = 0x4000c730;
+__env_lock = 0x40001fd4;
+__env_unlock = 0x40001fe0;
+fclose = 0x400020ac;
+_fclose_r = 0x40001fec;
+fflush = 0x40059394;
+_fflush_r = 0x40059320;
+_findenv_r = 0x40001f44;
+__fp_lock_all = 0x40001f1c;
+__fp_unlock_all = 0x40001f30;
+__fputwc = 0x40058da0;
+fputwc = 0x40058ea8;
+_fputwc_r = 0x40058e4c;
+_fwalk = 0x4000c738;
+_fwalk_reent = 0x4000c770;
+_getenv_r = 0x40001fbc;
+isalnum = 0x40000f04;
+isalpha = 0x40000f18;
+isascii = 0x4000c20c;
+isblank = 0x40000f2c;
+iscntrl = 0x40000f50;
+isdigit = 0x40000f64;
+isgraph = 0x40000f94;
+islower = 0x40000f78;
+isprint = 0x40000fa8;
+ispunct = 0x40000fc0;
+isspace = 0x40000fd4;
+isupper = 0x40000fe8;
+__itoa = 0x40056678;
+itoa = 0x400566b4;
+labs = 0x40056370;
+ldiv = 0x40056378;
+longjmp = 0x400562cc;
+memccpy = 0x4000c220;
+memchr = 0x4000c244;
+memcmp = 0x4000c260;
+memcpy = 0x4000c2c8;
+memmove = 0x4000c3c0;
+memrchr = 0x4000c400;
+memset = 0x4000c44c;
+qsort = 0x40056424;
+rand = 0x40001058;
+rand_r = 0x400010d4;
+__sccl = 0x4000c498;
+__sclose = 0x400011b8;
+__seofread = 0x40001148;
+setjmp = 0x40056268;
+__sflush_r = 0x400591e0;
+__sfmoreglue = 0x40001dc8;
+__sfp = 0x40001e90;
+__sfp_lock_acquire = 0x40001e08;
+__sfp_lock_release = 0x40001e14;
+__sinit = 0x40001e38;
+__sinit_lock_acquire = 0x40001e20;
+__sinit_lock_release = 0x40001e2c;
+srand = 0x40001004;
+__sread = 0x40001118;
+__sseek = 0x40001184;
+strcasecmp = 0x400011cc;
+strcasestr = 0x40001210;
+strcat = 0x4000c518;
+strchr = 0x4000c53c;
+strcmp = 0x40001274;
+strcoll = 0x40001398;
+strcpy = 0x400013ac;
+strcspn = 0x4000c558;
+strdup = 0x4000143c;
+_strdup_r = 0x40001450;
+strlcat = 0x40001470;
+strlcpy = 0x4000c584;
+strlen = 0x400014c0;
+strlwr = 0x40001524;
+strncasecmp = 0x40001550;
+strncat = 0x4000c5c4;
+strncmp = 0x4000c5f4;
+strncpy = 0x400015d4;
+strndup = 0x400016b0;
+_strndup_r = 0x400016c4;
+strnlen = 0x4000c628;
+strrchr = 0x40001708;
+strsep = 0x40001734;
+strspn = 0x4000c648;
+strstr = 0x4000c674;
+__strtok_r = 0x4000c6a8;
+strtok_r = 0x4000c70c;
+strtol = 0x4005681c;
+_strtol_r = 0x40056714;
+strtoul = 0x4005692c;
+_strtoul_r = 0x40056834;
+strupr = 0x4000174c;
+__submore = 0x40058f3c;
+__swbuf = 0x40058cb4;
+__swbuf_r = 0x40058bec;
+__swrite = 0x40001150;
+toascii = 0x4000c720;
+tolower = 0x40001868;
+toupper = 0x40001884;
+ungetc = 0x400590f4;
+_ungetc_r = 0x40058fa0;
+__utoa = 0x400561f0;
+utoa = 0x40056258;
+wcrtomb = 0x40058920;
+_wcrtomb_r = 0x400588d8;
+_wctomb_r = 0x40058f14;

targets/esp32.rom.newlib-locale.ld

@@ -0,0 +1,19 @@
+/* These are the locale-related newlib functions present in ESP32 ROM.
+   ESP32 ROM contains newlib version 2.2.0, and these functions should not be
+   used when compiling with newlib version 3, since locale implementation is
+   different there.
+
+   Unlike other ROM functions which are exported using PROVIDE, which declares
+   weak symbols, newlib related functions are exported using assignment,
+   which declares strong symbols. This is done so that ROM functions are always
+   used instead of the ones provided by libc.a.
+ */
+
+__locale_charset = 0x40059540;
+__locale_cjk_lang = 0x40059558;
+localeconv = 0x4005957c;
+_localeconv_r = 0x40059560;
+__locale_mb_cur_max = 0x40059548;
+__locale_msgcharset = 0x40059550;
+setlocale = 0x40059568;
+_setlocale_r = 0x4005950c;

targets/esp32.rom.newlib-nano.ld

@@ -0,0 +1,115 @@
+/* These are the printf/scanf related newlib functions present in ESP32 ROM.
+   These functions are compiled with newlib "nano" format option.
+   As such, they don's support 64-bit integer formats.
+   Floating point formats are supported by setting _printf_float and
+   _scanf_float entries in syscall table. This is done automatically
+   by startup code.
+   These functions should not be used when compiling with PSRAM cache workaround enabled.
+   See also esp32.rom.newlib-data.ld for the list of .data/.bss symbols
+   used by newlib functions, and esp32.rom.newlib-funcs.ld for the list
+   of general newlib functions.
+
+   Unlike other ROM functions which are exported using PROVIDE, which declares
+   weak symbols, newlib related functions are exported using assignment,
+   which declares strong symbols. This is done so that ROM functions are always
+   used instead of the ones provided by libc.a.
+ */
+
+asiprintf = 0x40056d9c;
+_asiprintf_r = 0x40056d4c;
+asniprintf = 0x40056cd8;
+_asniprintf_r = 0x40056c64;
+asnprintf = 0x40056cd8;
+_asnprintf_r = 0x40056c64;
+asprintf = 0x40056d9c;
+_asprintf_r = 0x40056d4c;
+fiprintf = 0x40056efc;
+_fiprintf_r = 0x40056ed8;
+fiscanf = 0x40058884;
+_fiscanf_r = 0x400588b4;
+fprintf = 0x40056efc;
+_fprintf_r = 0x40056ed8;
+fscanf = 0x40058884;
+_fscanf_r = 0x400588b4;
+iprintf = 0x40056978;
+_iprintf_r = 0x40056944;
+iscanf = 0x40058760;
+_iscanf_r = 0x4005879c;
+printf = 0x40056978;
+_printf_common = 0x40057338;
+_printf_i = 0x40057404;
+_printf_r = 0x40056944;
+scanf = 0x40058760;
+_scanf_chars = 0x40058384;
+_scanf_i = 0x4005845c;
+_scanf_r = 0x4005879c;
+__sfputs_r = 0x40057790;
+siprintf = 0x40056c08;
+_siprintf_r = 0x40056bbc;
+siscanf = 0x400587d0;
+_siscanf_r = 0x40058830;
+sniprintf = 0x40056b4c;
+_sniprintf_r = 0x40056ae4;
+snprintf = 0x40056b4c;
+_snprintf_r = 0x40056ae4;
+sprintf = 0x40056c08;
+_sprintf_r = 0x40056bbc;
+__sprint_r = 0x400577e4;
+sscanf = 0x400587d0;
+_sscanf_r = 0x40058830;
+__ssprint_r = 0x40056ff8;
+__ssputs_r = 0x40056f2c;
+__ssrefill_r = 0x40057fec;
+__ssvfiscanf_r = 0x4005802c;
+__ssvfscanf_r = 0x4005802c;
+_sungetc_r = 0x40057f6c;
+_svfiprintf_r = 0x40057100;
+__svfiscanf_r = 0x40057b08;
+_svfprintf_r = 0x40057100;
+__svfscanf = 0x40057f04;
+__svfscanf_r = 0x40057b08;
+vasiprintf = 0x40056eb8;
+_vasiprintf_r = 0x40056e80;
+vasniprintf = 0x40056e58;
+_vasniprintf_r = 0x40056df8;
+vasnprintf = 0x40056e58;
+_vasnprintf_r = 0x40056df8;
+vasprintf = 0x40056eb8;
+_vasprintf_r = 0x40056e80;
+vfiprintf = 0x40057ae8;
+_vfiprintf_r = 0x40057850;
+vfiscanf = 0x40057eb8;
+_vfiscanf_r = 0x40057f24;
+vfprintf = 0x40057ae8;
+_vfprintf_r = 0x40057850;
+vfscanf = 0x40057eb8;
+_vfscanf_r = 0x40057f24;
+viprintf = 0x400569b4;
+_viprintf_r = 0x400569e4;
+viscanf = 0x40058698;
+_viscanf_r = 0x400586c8;
+vprintf = 0x400569b4;
+_vprintf_r = 0x400569e4;
+vscanf = 0x40058698;
+_vscanf_r = 0x400586c8;
+vsiprintf = 0x40056ac4;
+_vsiprintf_r = 0x40056a90;
+vsiscanf = 0x40058740;
+_vsiscanf_r = 0x400586f8;
+vsniprintf = 0x40056a68;
+_vsniprintf_r = 0x40056a14;
+vsnprintf = 0x40056a68;
+_vsnprintf_r = 0x40056a14;
+vsprintf = 0x40056ac4;
+_vsprintf_r = 0x40056a90;
+vsscanf = 0x40058740;
+_vsscanf_r = 0x400586f8;
+
+/* _print_float and _scanf_float functions in ROM are stubs which call
+   real implementations in IDF through the syscall table.
+   As such, don't include these ROM symbols.
+
+_printf_float = 0x4000befc;
+_scanf_float = 0x4000bf18;
+
+*/

targets/esp32.rom.newlib-time.ld

@@ -0,0 +1,38 @@
+/* These are the newlib functions and the .bss/.data symbols necessary for these functions present in ESP32 ROM.
+   They should not be used when you need to solve the Y2K38 problem.
+   Because these functions were compiled with 32-bit width for the time_t structure.
+ */
+
+asctime = 0x40059588;
+asctime_r = 0x40000ec8;
+ctime = 0x400595b0;
+ctime_r = 0x400595c4;
+__gettzinfo = 0x40001fcc;
+__get_current_time_locale = 0x40001834;
+gmtime = 0x40059848;
+gmtime_r = 0x40059868;
+localtime = 0x400595dc;
+localtime_r = 0x400595fc;
+mktime = 0x4005a5e8;
+strftime = 0x40059ab4;
+time = 0x40001844;
+__time_load_locale = 0x4000183c;
+tzset = 0x40001a1c;
+_tzset_r = 0x40001a28;
+__tzcalc_limits = 0x400018a0;
+__tz_lock = 0x40001a04;
+__tz_unlock = 0x40001a10;
+/* The .bss/.data symbols necessary for these functions */
+_timezone = 0x3ffae0a0;
+_tzname = 0x3ffae030;
+_daylight = 0x3ffae0a4;
+__month_lengths = 0x3ff9609c;
+
+/* These functions don't use time_t, but use other structures which include time_t.
+ * For example, 'struct stat' contains time_t.
+ */
+_isatty_r = 0x40000ea0;
+__sfvwrite_r = 0x4005893c;
+__smakebuf_r = 0x40059108;
+__srefill_r = 0x400593d4;
+__swsetup_r = 0x40058cc8;