diff --git a/app/actions.cpp b/app/actions.cpp
index 53bdeb05..a53fd35e 100644
--- a/app/actions.cpp
+++ b/app/actions.cpp
@@ -932,7 +932,7 @@ namespace Action {
 
         const Params::PreviewNumbers& numbers = Params::instance().previewNumbers_;
         for (auto number : numbers) {
-            size_t num = static_cast<size_t>(number);
+            auto num = static_cast<size_t>(number);
             if (num == 0) {
                 // Write all previews
                 for (num = 0; num < pvList.size(); ++num) {
diff --git a/app/exiv2.cpp b/app/exiv2.cpp
index 1d5f9035..48d19687 100644
--- a/app/exiv2.cpp
+++ b/app/exiv2.cpp
@@ -150,7 +150,7 @@ int main(int argc, char* const argv[])
         assert(task);
 
         // Process all files
-        int s = static_cast<int>(params.files_.size());
+        auto s = static_cast<int>(params.files_.size());
         if (params.action_ & Action::extract && params.target_ & Params::ctStdInOut && s > 1) {
             std::cerr << params.progname() << ": " << _("Only one file is allowed when extracting to stdout") << std::endl;
             rc = 1;
@@ -949,7 +949,7 @@ static int readFileToBuf(FILE* f,Exiv2::DataBuf& buf)
     bool more {true};
     while   ( more ) {
         char buff[buff_size];
-        int n = static_cast<int>(fread(buff, 1, buff_size, f));
+        auto n = static_cast<int>(fread(buff, 1, buff_size, f));
         more       = n > 0 ;
         if ( more ) {
             bytes.resize(nBytes+n);
@@ -1270,7 +1270,7 @@ namespace {
             }
             if (k > i) {
                 bool ok = false;
-                int num = Exiv2::stringTo<int>(os.str(), ok);
+                auto num = Exiv2::stringTo<int>(os.str(), ok);
                 if (ok && num >= 0) {
                     previewNumbers.insert(num);
                 }
@@ -1282,7 +1282,7 @@ namespace {
             }
             if (!(k < optArg.size() && optArg[i] == ',')) break;
         }
-        int ret = static_cast<int>(k - j);
+        auto ret = static_cast<int>(k - j);
         if (ret == 0) {
             previewNumbers.insert(0);
         }
diff --git a/samples/exiv2json.cpp b/samples/exiv2json.cpp
index ba754c0c..47e24356 100644
--- a/samples/exiv2json.cpp
+++ b/samples/exiv2json.cpp
@@ -308,7 +308,7 @@ int main(int argc, char* const argv[])
 
         if ( option == 'a' || option == 'i' ) {
             Exiv2::IptcData &iptcData = image->iptcData();
-            for (Exiv2::IptcData::const_iterator i = iptcData.begin(); i != iptcData.end(); ++i) {
+            for (auto i = iptcData.begin(); i != iptcData.end(); ++i) {
                 std::string name   ;
                 Jzon::Node& object = objectForKey(i->key(),root,name);
                 push(object,name,i);
diff --git a/samples/geotag.cpp b/samples/geotag.cpp
index 544dad44..c94dbb32 100644
--- a/samples/geotag.cpp
+++ b/samples/geotag.cpp
@@ -247,13 +247,13 @@ std::string Position::toExifString(double d,bool bRational,bool bLat)
     const char* EW   = d>=0.0?"E":"W";
     const char* NSEW = bLat  ? NS: EW;
     if ( d < 0 ) d = -d;
-    int deg = static_cast<int>(d);
+    auto deg = static_cast<int>(d);
     d -= deg;
     d *= 60;
-    int min = static_cast<int>(d);
+    auto min = static_cast<int>(d);
     d -= min;
     d *= 60;
-    int sec = static_cast<int>(d);
+    auto sec = static_cast<int>(d);
     char result[200];
     if ( bRational )
         snprintf(result,sizeof(result),"%d/1 %d/1 %d/1" ,deg,min,sec);
diff --git a/samples/getopt-test.cpp b/samples/getopt-test.cpp
index 48d5f6bb..690302a1 100644
--- a/samples/getopt-test.cpp
+++ b/samples/getopt-test.cpp
@@ -114,7 +114,7 @@ int main(int argc, char** const argv)
 	do {
 	    n = ::getopt(argc,argv,::optstring);
 	    if ( n >= 0 ) {
-            char N = static_cast<char>(n);
+            auto N = static_cast<char>(n);
             std::cout << n << " = " << N;
         } else {
             std::cout << n ;
@@ -132,7 +132,7 @@ int main(int argc, char** const argv)
 	do {
 	    n = Util::getopt(argc,argv,::optstring);
 	    if ( n >= 0 ) {
-            char N = static_cast<char>(n);
+            auto N = static_cast<char>(n);
             std::cout << n << " = " << N;
         } else {
             std::cout << n ;
diff --git a/samples/iotest.cpp b/samples/iotest.cpp
index 56277355..7a7b8a5e 100644
--- a/samples/iotest.cpp
+++ b/samples/iotest.cpp
@@ -189,7 +189,7 @@ int WriteReadSeek(BasicIo &io)
         std::cerr << ": WRS size is not " << size1 << "\n";
         return 2;
     }
-    long backup = static_cast<long>(size1);
+    auto backup = static_cast<long>(size1);
     io.seek(-backup, BasicIo::cur);
 
     int c = EOF;
diff --git a/samples/mmap-test.cpp b/samples/mmap-test.cpp
index e0ab5997..ae218431 100644
--- a/samples/mmap-test.cpp
+++ b/samples/mmap-test.cpp
@@ -47,7 +47,7 @@ try {
     }
     // Map it to memory
     const Exiv2::byte* pData = file.mmap();
-    long size = static_cast<long>(file.size());
+    auto size = static_cast<long>(file.size());
     DataBuf buf(size);
     // Read from the memory mapped region
     buf.copyBytes(0, pData, buf.size());
diff --git a/src/basicio.cpp b/src/basicio.cpp
index 7532af85..ee202a2b 100644
--- a/src/basicio.cpp
+++ b/src/basicio.cpp
@@ -1263,7 +1263,7 @@ namespace Exiv2 {
         }
 
         // submit to the remote machine.
-        long dataSize = static_cast<long>(src.size() - left - right);
+        auto dataSize = static_cast<long>(src.size() - left - right);
         if (dataSize > 0) {
             auto data = static_cast<byte*>(std::malloc(dataSize));
             src.seek(left, BasicIo::beg);
diff --git a/src/bmffimage.cpp b/src/bmffimage.cpp
index 2b87753a..61f92dda 100644
--- a/src/bmffimage.cpp
+++ b/src/bmffimage.cpp
@@ -217,7 +217,7 @@ namespace Exiv2
         enforce(box_length >= hdrsize, Exiv2::kerCorruptedMetadata);
         enforce(box_length - hdrsize <= static_cast<uint64_t>(pbox_end - restore), Exiv2::kerCorruptedMetadata);
 
-        const size_t buffer_size = static_cast<size_t>(box_length - hdrsize);
+        const auto buffer_size = static_cast<size_t>(box_length - hdrsize);
         if (skipBox(box_type)) {
             if (bTrace) {
                 out << std::endl;
@@ -637,7 +637,7 @@ namespace Exiv2
         xmpID_     = unknownID_;
 
         long address = 0;
-        const long file_end = static_cast<long>(io_->size());
+        const auto file_end = static_cast<long>(io_->size());
         while (address < file_end) {
             io_->seek(address, BasicIo::beg);
             address = boxHandler(std::cout,kpsNone,file_end,0);
@@ -671,7 +671,7 @@ namespace Exiv2
                 IoCloser closer(*io_);
 
                 long   address = 0;
-                const long file_end = static_cast<long>(io_->size());
+                const auto file_end = static_cast<long>(io_->size());
                 while (address < file_end) {
                     io_->seek(address, BasicIo::beg);
                     address = boxHandler(out,option,file_end,depth);
diff --git a/src/canonmn_int.cpp b/src/canonmn_int.cpp
index ce7cf9fd..260dd688 100644
--- a/src/canonmn_int.cpp
+++ b/src/canonmn_int.cpp
@@ -2730,8 +2730,8 @@ namespace Exiv2::Internal {
             return os;
         }
 
-        int const exifFlMin = static_cast<int>(static_cast<float>(pos->value().toInt64(1)) / pos->value().toFloat(2));
-        int const exifFlMax = static_cast<int>(static_cast<float>(pos->value().toInt64(0)) / pos->value().toFloat(2));
+        auto const exifFlMin = static_cast<int>(static_cast<float>(pos->value().toInt64(1)) / pos->value().toFloat(2));
+        auto const exifFlMax = static_cast<int>(static_cast<float>(pos->value().toInt64(0)) / pos->value().toFloat(2));
 
         ExifKey aperKey("Exif.CanonCs.MaxAperture");
         pos = metadata->findKey(aperKey);
@@ -2894,7 +2894,7 @@ namespace Exiv2::Internal {
             // see also printSi0x0017
             std::ostringstream oss;
             oss.copyfmt(os);
-            int res = static_cast<int>(100.0 * (static_cast<short>(value.toInt64()) / 32.0 + 5.0) + 0.5);
+            auto res = static_cast<int>(100.0 * (static_cast<short>(value.toInt64()) / 32.0 + 5.0) + 0.5);
             os << std::fixed << std::setprecision(2) << res / 100.0;
             os.copyfmt(oss);
         }
@@ -3067,7 +3067,7 @@ namespace Exiv2::Internal {
         // remove fraction
         const auto remainder = val & 0x1f;
         val -= remainder;
-        float frac = static_cast<float>(remainder);
+        auto frac = static_cast<float>(remainder);
         // convert 1/3 (0x0c) and 2/3 (0x14) codes
         if (frac == 0x0c) {
             frac = 32.0F / 3;
diff --git a/src/casiomn_int.cpp b/src/casiomn_int.cpp
index bfbbc207..520bf6e1 100644
--- a/src/casiomn_int.cpp
+++ b/src/casiomn_int.cpp
@@ -527,7 +527,7 @@ namespace Exiv2::Internal {
         std::vector<char> numbers;
         for(size_t i=0; i<value.size(); i++)
         {
-            const char l = static_cast<char>(value.toInt64(i));
+            const auto l = static_cast<char>(value.toInt64(i));
             if(l!=0)
             {
                 numbers.push_back(l);
diff --git a/src/convert.cpp b/src/convert.cpp
index ae8cb862..80d07bab 100644
--- a/src/convert.cpp
+++ b/src/convert.cpp
@@ -774,7 +774,7 @@ namespace Exiv2 {
             deg[i] = static_cast<double>(z)/d;
         }
         double min = deg[0] * 60.0 + deg[1] + deg[2] / 60.0;
-        int ideg = static_cast<int>(min / 60.0);
+        auto ideg = static_cast<int>(min / 60.0);
         min -= ideg * 60;
         std::ostringstream oss;
         oss << ideg << ","
diff --git a/src/crwimage_int.cpp b/src/crwimage_int.cpp
index 3088e0c9..82e414c7 100644
--- a/src/crwimage_int.cpp
+++ b/src/crwimage_int.cpp
@@ -816,7 +816,7 @@ namespace Exiv2::Internal {
         const uint32_t component_size = ciffComponent.size();
         enforce(component_size % 2 == 0, kerCorruptedMetadata);
         enforce(component_size/2 <= static_cast<uint32_t>(std::numeric_limits<uint16_t>::max()), kerCorruptedMetadata);
-        const uint16_t num_components = static_cast<uint16_t>(component_size/2);
+        const auto num_components = static_cast<uint16_t>(component_size / 2);
         uint16_t c = 1;
         while (c < num_components) {
             uint16_t n = 1;
diff --git a/src/http.cpp b/src/http.cpp
index 1fbcf8c0..9eecfcac 100644
--- a/src/http.cpp
+++ b/src/http.cpp
@@ -227,7 +227,7 @@ int Exiv2::http(Exiv2::Dictionary& request,Exiv2::Dictionary& response,std::stri
 
     ////////////////////////////////////
     // open the socket
-    int sockfd = static_cast<int>(socket(AF_INET , SOCK_STREAM,IPPROTO_TCP));
+    auto sockfd = static_cast<int>(socket(AF_INET, SOCK_STREAM, IPPROTO_TCP));
     if (sockfd < 0)
         return error(errors, "unable to create socket\n", nullptr, nullptr, 0);
 
diff --git a/src/image.cpp b/src/image.cpp
index 470769d4..9197d9e6 100644
--- a/src/image.cpp
+++ b/src/image.cpp
@@ -386,7 +386,7 @@ namespace Exiv2 {
                 // Overflow check
                 enforce(allocate64 <= static_cast<uint64_t>(std::numeric_limits<uint32_t>::max()), kerCorruptedMetadata);
                 enforce(allocate64 <= static_cast<uint64_t>(std::numeric_limits<long>::max()), kerCorruptedMetadata);
-                const long allocate = static_cast<long>(allocate64);
+                const auto allocate = static_cast<long>(allocate64);
                 DataBuf  buf(allocate);  // allocate a buffer
                 buf.copyBytes(0, dir.c_data(8), 4);  // copy dir[8:11] into buffer (short strings)
 
@@ -517,7 +517,7 @@ namespace Exiv2 {
 
             // read header (we already know for certain that we have a Tiff file)
             io.readOrThrow(dir.data(),  8, kerCorruptedMetadata);
-            char c = static_cast<char>(dir.read_uint8(0));
+            auto c = static_cast<char>(dir.read_uint8(0));
             bool bSwap   = ( c == 'M' && isLittleEndianPlatform() )
                         || ( c == 'I' && isBigEndianPlatform()    )
                         ;
diff --git a/src/jpgimage.cpp b/src/jpgimage.cpp
index 384a327e..8b08ce3b 100644
--- a/src/jpgimage.cpp
+++ b/src/jpgimage.cpp
@@ -398,8 +398,8 @@ namespace Exiv2 {
                     foundIccData = true ;
                     --search ;
                 }
-                int chunk = static_cast<int>(buf.read_uint8(2 + 12));
-                int chunks = static_cast<int>(buf.read_uint8(2 + 13));
+                auto chunk = static_cast<int>(buf.read_uint8(2 + 12));
+                auto chunks = static_cast<int>(buf.read_uint8(2 + 13));
                 // ICC1v43_2010-12.pdf header is 14 bytes
                 // header = "ICC_PROFILE\0" (12 bytes)
                 // chunk/chunks are a single byte
@@ -1082,7 +1082,7 @@ namespace Exiv2 {
                         if (chunkSize > maxChunkSize) {
                             chunkSize = maxChunkSize;
                             // Don't break at a valid IRB boundary
-                            const long writtenSize = static_cast<long>(chunkStart - newPsData.c_data());
+                            const auto writtenSize = static_cast<long>(chunkStart - newPsData.c_data());
                             if (Photoshop::valid(newPsData.c_data(), writtenSize + chunkSize)) {
                                 // Since an IRB has minimum size 12,
                                 // (chunkSize - 8) can't be also a IRB boundary
diff --git a/src/nikonmn_int.cpp b/src/nikonmn_int.cpp
index 460f1b91..2efc1b06 100644
--- a/src/nikonmn_int.cpp
+++ b/src/nikonmn_int.cpp
@@ -2623,7 +2623,7 @@ fmountlens[] = {
      */
         if (metadata == nullptr)
         {
-            const unsigned char vid = static_cast<unsigned char>(value.toInt64(0));
+            const auto vid = static_cast<unsigned char>(value.toInt64(0));
 
             /* the 'FMntLens' name is added to the anonymous struct for
              * fmountlens[]
diff --git a/src/olympusmn_int.cpp b/src/olympusmn_int.cpp
index decf3ea5..c04ffa04 100644
--- a/src/olympusmn_int.cpp
+++ b/src/olympusmn_int.cpp
@@ -1361,9 +1361,9 @@ namespace Exiv2::Internal {
             return os << value;
         }
 
-        byte v0 = static_cast<byte>(value.toInt64(0));
-        byte v2 = static_cast<byte>(value.toInt64(2));
-        byte v3 = static_cast<byte>(value.toInt64(3));
+        auto v0 = static_cast<byte>(value.toInt64(0));
+        auto v2 = static_cast<byte>(value.toInt64(2));
+        auto v3 = static_cast<byte>(value.toInt64(3));
 
         for (auto&& type : lensTypes) {
             if (type.val[0] == v0 && type.val[1] == v2 && type.val[2] == v3) {
@@ -1407,8 +1407,8 @@ namespace Exiv2::Internal {
             return os << value;
         }
 
-        byte v0 = static_cast<byte>(value.toInt64(0));
-        byte v2 = static_cast<byte>(value.toInt64(2));
+        auto v0 = static_cast<byte>(value.toInt64(0));
+        auto v2 = static_cast<byte>(value.toInt64(2));
 
         for (auto&& model : extenderModels) {
             if (model.val[0] == v0 && model.val[1] == v2) {
diff --git a/src/panasonicmn_int.cpp b/src/panasonicmn_int.cpp
index 1bcbde5c..4d15ea14 100644
--- a/src/panasonicmn_int.cpp
+++ b/src/panasonicmn_int.cpp
@@ -672,14 +672,14 @@ namespace Exiv2::Internal {
     std::ostream& PanasonicMakerNote::printAccelerometer(std::ostream& os, const Value& value, const ExifData*)
     {
         // value is stored as unsigned int, but should be read as int16_t.
-        const int16_t i = static_cast<int16_t>(value.toInt64());
+        const auto i = static_cast<int16_t>(value.toInt64());
         return os << i;
     }  // PanasonicMakerNote::printAccelerometer
 
     std::ostream& PanasonicMakerNote::printRollAngle(std::ostream& os, const Value& value, const ExifData*)
     {
         // value is stored as unsigned int, but should be read as int16_t.
-        const int16_t i = static_cast<int16_t>(value.toInt64());
+        const auto i = static_cast<int16_t>(value.toInt64());
         std::ostringstream oss;
         oss.copyfmt(os);
         os << std::fixed << std::setprecision(1) << i / 10.0;
@@ -691,7 +691,7 @@ namespace Exiv2::Internal {
     std::ostream& PanasonicMakerNote::printPitchAngle(std::ostream& os, const Value& value, const ExifData*)
     {
         // value is stored as unsigned int, but should be read as int16_t.
-        const int16_t i = static_cast<int16_t>(value.toInt64());
+        const auto i = static_cast<int16_t>(value.toInt64());
         std::ostringstream oss;
         oss.copyfmt(os);
         os << std::fixed << std::setprecision(1) << -i / 10.0;
diff --git a/src/pgfimage.cpp b/src/pgfimage.cpp
index 1582830a..2114e8cc 100644
--- a/src/pgfimage.cpp
+++ b/src/pgfimage.cpp
@@ -181,7 +181,7 @@ namespace Exiv2 {
         img->setIptcData(iptcData_);
         img->setXmpData(xmpData_);
         img->writeMetadata();
-        long imgSize = static_cast<long>(img->io().size());
+        auto imgSize = static_cast<long>(img->io().size());
         DataBuf imgBuf   = img->io().read(imgSize);
 
 #ifdef EXIV2_DEBUG_MESSAGES
@@ -257,7 +257,7 @@ namespace Exiv2 {
         if (bufRead != buffer.size())
             throw Error(kerInputDataReadFailed);
 
-        int headerSize = static_cast<int>(byteSwap_(buffer, 0, bSwap_));
+        auto headerSize = static_cast<int>(byteSwap_(buffer, 0, bSwap_));
         if (headerSize <= 0 ) throw Error(kerNoImageInInputData);
 
 #ifdef EXIV2_DEBUG_MESSAGES
diff --git a/src/pngchunk_int.cpp b/src/pngchunk_int.cpp
index 8648cece..81cdfcae 100644
--- a/src/pngchunk_int.cpp
+++ b/src/pngchunk_int.cpp
@@ -158,7 +158,7 @@ namespace Exiv2::Internal {
                             Exiv2::kerCorruptedMetadata);
 
                     const byte* text = data.c_data(keysize + 3 + languageTextSize + 1 + translatedKeyTextSize + 1);
-                    const long textsize = static_cast<long>(
+                    const auto textsize = static_cast<long>(
                         data.size() - (keysize + 3 + languageTextSize + 1 + translatedKeyTextSize + 1));
 
                     if (compressionFlag == 0x00) {
diff --git a/src/pngimage.cpp b/src/pngimage.cpp
index d4b85d53..74df305a 100644
--- a/src/pngimage.cpp
+++ b/src/pngimage.cpp
@@ -313,7 +313,7 @@ namespace Exiv2 {
                                     1; // leading string length
                     enforce(name_l < dataOffset, kerCorruptedMetadata);
 
-                    uint32_t  start  = static_cast<uint32_t>(name_l);
+                    auto start = static_cast<uint32_t>(name_l);
                     bool      bLF    = false;
 
                     // decode the chunk
diff --git a/src/rafimage.cpp b/src/rafimage.cpp
index 76aece5d..75e7920f 100644
--- a/src/rafimage.cpp
+++ b/src/rafimage.cpp
@@ -301,8 +301,8 @@ namespace Exiv2 {
                 kerCorruptedMetadata);
 #endif
 
-        long jpg_img_off = static_cast<long>(jpg_img_off_u32);
-        long jpg_img_len = static_cast<long>(jpg_img_len_u32);
+        auto jpg_img_off = static_cast<long>(jpg_img_off_u32);
+        auto jpg_img_len = static_cast<long>(jpg_img_len_u32);
 
         enforce(jpg_img_len >= 12, kerCorruptedMetadata);
 
diff --git a/src/tags_int.cpp b/src/tags_int.cpp
index bc4cbe91..d1617b9a 100644
--- a/src/tags_int.cpp
+++ b/src/tags_int.cpp
@@ -2784,9 +2784,9 @@ namespace Exiv2::Internal {
             if (fraction != 0) p = 1;
             const double ss = std::fmod(t, 60);
             const double minutes = (t - ss)/60;
-            const int mm = static_cast<int>(std::fmod(minutes, 60));
+            const auto mm = static_cast<int>(std::fmod(minutes, 60));
             const double hours = (minutes - mm)/60;
-            const int hh = static_cast<int>(std::fmod(hours, 24));
+            const auto hh = static_cast<int>(std::fmod(hours, 24));
 
             os << std::setw(2) << std::setfill('0') << std::right << hh << ":"
                << std::setw(2) << std::setfill('0') << std::right << mm << ":"
diff --git a/src/tiffcomposite_int.cpp b/src/tiffcomposite_int.cpp
index 290b1060..d72dcba1 100644
--- a/src/tiffcomposite_int.cpp
+++ b/src/tiffcomposite_int.cpp
@@ -1077,7 +1077,7 @@ namespace Exiv2::Internal {
             }
             // Also add the size of data, but only if needed
             if (isRootDir) {
-                uint32_t sd = static_cast<uint32_t>(component->sizeData());
+                auto sd = static_cast<uint32_t>(component->sizeData());
                 sd += sd & 1;               // Align data to word boundary
                 sizeData += sd;
             }
@@ -1104,7 +1104,7 @@ namespace Exiv2::Internal {
                 sv += sv & 1;               // Align value to word boundary
                 valueIdx += sv;
             }
-            uint32_t sd = static_cast<uint32_t>(component->sizeData());
+            auto sd = static_cast<uint32_t>(component->sizeData());
             sd += sd & 1;                   // Align data to word boundary
             dataIdx += sd;
         }
@@ -1134,7 +1134,7 @@ namespace Exiv2::Internal {
                 idx += sv;
                 valueIdx += sv;
             }
-            uint32_t sd = static_cast<uint32_t>(component->sizeData());
+            auto sd = static_cast<uint32_t>(component->sizeData());
             sd += sd & 1;                   // Align data to word boundary
             dataIdx += sd;
         }
@@ -1626,7 +1626,7 @@ namespace Exiv2::Internal {
                 sv += sv & 1;               // Align value to word boundary
                 len += sv;
             }
-            uint32_t sd = static_cast<uint32_t>(component->sizeData());
+            auto sd = static_cast<uint32_t>(component->sizeData());
             sd += sd & 1;                   // Align data to word boundary
             len += sd;
         }
diff --git a/src/tiffvisitor_int.cpp b/src/tiffvisitor_int.cpp
index fd3f4323..f66bd4f0 100644
--- a/src/tiffvisitor_int.cpp
+++ b/src/tiffvisitor_int.cpp
@@ -1521,7 +1521,7 @@ namespace Exiv2::Internal {
         if (count > std::numeric_limits<uint32_t>::max() / typeSize) {
             throw Error(kerArithmeticOverflow);
         }
-        uint32_t size = static_cast<uint32_t>(typeSize * count);
+        auto size = static_cast<uint32_t>(typeSize * count);
         uint32_t offset = getLong(p, byteOrder());
         byte* pData = p;
         if (   size > 4
diff --git a/src/types.cpp b/src/types.cpp
index a522dc54..8f6ba372 100644
--- a/src/types.cpp
+++ b/src/types.cpp
@@ -628,13 +628,13 @@ namespace Exiv2 {
 
     int64_t parseInt64(const std::string& s, bool& ok)
     {
-        int64_t ret = stringTo<int64_t>(s, ok);
+        auto ret = stringTo<int64_t>(s, ok);
         if (ok) return ret;
 
         auto f = stringTo<float>(s, ok);
         if (ok) return static_cast<int64_t>(f);
 
-        Rational r = stringTo<Rational>(s, ok);
+        auto r = stringTo<Rational>(s, ok);
         if (ok) {
             if (r.second <= 0) {
                 ok = false;
@@ -664,7 +664,7 @@ namespace Exiv2 {
         auto ret = stringTo<float>(s, ok);
         if (ok) return ret;
 
-        Rational r = stringTo<Rational>(s, ok);
+        auto r = stringTo<Rational>(s, ok);
         if (ok) {
             if (r.second == 0) {
                 ok = false;
@@ -683,10 +683,10 @@ namespace Exiv2 {
 
     Rational parseRational(const std::string& s, bool& ok)
     {
-        Rational ret = stringTo<Rational>(s, ok);
+        auto ret = stringTo<Rational>(s, ok);
         if (ok) return ret;
 
-        long l = stringTo<long>(s, ok);
+        auto l = stringTo<long>(s, ok);
         if (ok)
             return {l, 1};
 
@@ -714,7 +714,7 @@ namespace Exiv2 {
         }
         // Beware: primitive conversion algorithm
         int32_t den = 1000000;
-        const long d_as_long = static_cast<long>(d);
+        const auto d_as_long = static_cast<long>(d);
         if (Safe::abs(d_as_long) > 2147) {
             den = 10000;
         }
diff --git a/src/value.cpp b/src/value.cpp
index f28e21d3..6b8b20ee 100644
--- a/src/value.cpp
+++ b/src/value.cpp
@@ -1001,7 +1001,7 @@ namespace Exiv2 {
         tms.tm_mday = date_.day;
         tms.tm_mon = date_.month - 1;
         tms.tm_year = date_.year - 1900;
-        int64_t l = static_cast<int64_t>(std::mktime(&tms));
+        auto l = static_cast<int64_t>(std::mktime(&tms));
         ok_ = (l != -1);
         return l;
     }
diff --git a/src/webpimage.cpp b/src/webpimage.cpp
index 35c3c40e..c4302335 100644
--- a/src/webpimage.cpp
+++ b/src/webpimage.cpp
@@ -208,7 +208,7 @@ namespace Exiv2 {
             // Check that `size_u32` is safe to cast to `long`.
             enforce(size_u32 <= static_cast<size_t>(std::numeric_limits<unsigned int>::max()),
                     Exiv2::kerCorruptedMetadata);
-            const long size = static_cast<long>(size_u32);
+            const auto size = static_cast<long>(size_u32);
             DataBuf payload(size);
             io_->readOrThrow(payload.data(), payload.size(), Exiv2::kerCorruptedMetadata);
             if ( payload.size() % 2 ) {
@@ -346,7 +346,7 @@ namespace Exiv2 {
             // Check that `size_u32` is safe to cast to `long`.
             enforce(size_u32 <= static_cast<size_t>(std::numeric_limits<unsigned int>::max()),
                     Exiv2::kerCorruptedMetadata);
-            const long size = static_cast<long>(size_u32);
+            const auto size = static_cast<long>(size_u32);
 
             DataBuf payload(size);
             io_->readOrThrow(payload.data(), size, Exiv2::kerCorruptedMetadata);
@@ -572,7 +572,7 @@ namespace Exiv2 {
 
             // Check that `size_u32` is safe to cast to `long`.
             enforce(size_u32 <= static_cast<uint32_t>(std::numeric_limits<long>::max()), Exiv2::kerCorruptedMetadata);
-            const long size = static_cast<long>(size_u32);
+            const auto size = static_cast<long>(size_u32);
 
             // Check that `size` is within bounds.
             enforce(io_->tell() <= filesize, Exiv2::kerCorruptedMetadata);