Fixed charset handling in reader for dep files

internal/arduino/builder/internal/utils/utils.go

@@ -16,6 +16,7 @@
 package utils
 
 import (
+	"internal/goos"
 	"os"
 	"strings"
 	"unicode"
@@ -96,57 +97,71 @@ func ObjFileIsUpToDate(sourceFile, objectFile, dependencyFile *paths.Path) (bool
 		return f.Filter(rows, f.NotEquals("")), nil
 	}
 
-	rows, err := readDepFileWithEncoding(nil)
-	if err != nil {
-		logrus.Debugf("Could not read dependency file: %s", dependencyFile)
-		return false, err
-	}
-	if len(rows) == 0 {
-		return true, nil
-	}
-
-	firstRow := rows[0]
-	if !strings.HasSuffix(firstRow, ":") {
-		logrus.Debugf("No colon in first line of depfile")
-		return false, nil
-	}
-	objFileInDepFile := firstRow[:len(firstRow)-1]
-	if objFileInDepFile != objectFile.String() {
-		logrus.Debugf("Depfile is about different object file: %v", objFileInDepFile)
-		return false, nil
-	}
-
-	// The first line of the depfile contains the path to the object file to generate.
-	// The second line of the depfile contains the path to the source file.
-	// All subsequent lines contain the header files necessary to compile the object file.
-
-	// If we don't do this check it might happen that trying to compile a source file
-	// that has the same name but a different path wouldn't recreate the object file.
-	if sourceFile.String() != strings.Trim(rows[1], " ") {
-		logrus.Debugf("Depfile is about different source file: %v", strings.Trim(rows[1], " "))
-		return false, nil
-	}
+	checkDepFileWithEncoding := func(mapping *charmap.Charmap) (bool, error) {
+		rows, err := readDepFileWithEncoding(mapping)
+		if err != nil {
+			logrus.Debugf("Could not read dependency file: %s", dependencyFile)
+			return false, err
+		}
+		if len(rows) == 0 {
+			return true, nil
+		}
 
-	rows = rows[1:]
-	for _, row := range rows {
-		depStat, err := os.Stat(row)
-		if err != nil && !os.IsNotExist(err) {
-			// There is probably a parsing error of the dep file
-			// Ignore the error and trigger a full rebuild anyway
-			logrus.WithError(err).Debugf("Failed to read: %v", row)
+		firstRow := rows[0]
+		if !strings.HasSuffix(firstRow, ":") {
+			logrus.Debugf("No colon in first line of depfile")
 			return false, nil
 		}
-		if os.IsNotExist(err) {
-			logrus.Debugf("Not found: %v", row)
+		objFileInDepFile := firstRow[:len(firstRow)-1]
+		if objFileInDepFile != objectFile.String() {
+			logrus.Debugf("Depfile is about different object file: %v", objFileInDepFile)
 			return false, nil
 		}
-		if depStat.ModTime().After(objectFileStat.ModTime()) {
-			logrus.Debugf("%v newer than %v", row, objectFile)
+
+		// The first line of the depfile contains the path to the object file to generate.
+		// The second line of the depfile contains the path to the source file.
+		// All subsequent lines contain the header files necessary to compile the object file.
+
+		// If we don't do this check it might happen that trying to compile a source file
+		// that has the same name but a different path wouldn't recreate the object file.
+		if sourceFile.String() != strings.Trim(rows[1], " ") {
+			logrus.Debugf("Depfile is about different source file: %v", strings.Trim(rows[1], " "))
 			return false, nil
 		}
+
+		rows = rows[1:]
+		for _, row := range rows {
+			depStat, err := os.Stat(row)
+			if err != nil && !os.IsNotExist(err) {
+				// There is probably a parsing error of the dep file
+				// Ignore the error and trigger a full rebuild anyway
+				logrus.WithError(err).Debugf("Failed to read: %v", row)
+				return false, nil
+			}
+			if os.IsNotExist(err) {
+				logrus.Debugf("Not found: %v", row)
+				return false, nil
+			}
+			if depStat.ModTime().After(objectFileStat.ModTime()) {
+				logrus.Debugf("%v newer than %v", row, objectFile)
+				return false, nil
+			}
+		}
+
+		return true, nil
 	}
 
-	return true, nil
+	// This is required because on Windows we don't know which enconding is used
+	// by gcc to write the dep file (it could be UTF-8 or any of the Windows
+	// default mappings. Would ISO8859_1 be enough? Or we should differentiate the
+	// various ISO8859_XX based on selected locale? Only time will tell...).
+	if goos.GOOS == "windows" {
+		if upToDate, err := checkDepFileWithEncoding(charmap.ISO8859_1); err != nil {
+			return upToDate, nil
+		}
+		// Fallback to UTF-8...
+	}
+	return checkDepFileWithEncoding(nil)
 }
 
 func removeEndingBackSlash(s string) string {