Fix warnings reported by -Wshadow=local (fixes #431)

14 files changed, 98 insertions, 114 deletions

diff --git a/examples/pdf-invert-images.cc b/examples/pdf-invert-images.cc
index 418598c7..3a0afca4 100644
--- a/examples/pdf-invert-images.cc
+++ b/examples/pdf-invert-images.cc
@@ -160,11 +160,9 @@ int main(int argc, char* argv[])
 	    // Get all images on the page.
 	    std::map<std::string, QPDFObjectHandle> images =
 		page.getPageImages();
-	    for (std::map<std::string, QPDFObjectHandle>::iterator iter =
-		     images.begin();
-		 iter != images.end(); ++iter)
+	    for (auto& iter2: images)
 	    {
-		QPDFObjectHandle& image = (*iter).second;
+		QPDFObjectHandle& image = iter2.second;
 		QPDFObjectHandle image_dict = image.getDict();
 		QPDFObjectHandle color_space =
 		    image_dict.getKey("/ColorSpace");
diff --git a/examples/pdf-mod-info.cc b/examples/pdf-mod-info.cc
index 0585e9fd..9ffd4ede 100644
--- a/examples/pdf-mod-info.cc
+++ b/examples/pdf-mod-info.cc
@@ -46,8 +46,7 @@ void dumpInfoDict(QPDF& pdf,
 	{
 	    QPDFObjectHandle elt = info.getKey(*it);
 	    std::string val;
-	    if (false) {}
-	    else if (elt.isString())
+	    if (elt.isString())
 	    {
 		val = elt.getStringValue();
 	    }
diff --git a/examples/pdf-split-pages.cc b/examples/pdf-split-pages.cc
index f8997bbe..ea1c92bc 100644
--- a/examples/pdf-split-pages.cc
+++ b/examples/pdf-split-pages.cc
@@ -15,7 +15,6 @@
 #include <string>
 #include <cstring>
 
-static char const* whoami = 0;
 static bool static_id = false;
 
 static void process(char const* whoami,
@@ -50,7 +49,7 @@ static void process(char const* whoami,
     }
 }
 
-void usage()
+void usage(char const* whoami)
 {
     std::cerr << "Usage: " << whoami << " infile outprefix" << std::endl;
     exit(2);
@@ -58,7 +57,7 @@ void usage()
 
 int main(int argc, char* argv[])
 {
-    whoami = QUtil::getWhoami(argv[0]);
+    char const* whoami = QUtil::getWhoami(argv[0]);
 
     // For libtool's sake....
     if (strncmp(whoami, "lt-", 3) == 0)
@@ -75,7 +74,7 @@ int main(int argc, char* argv[])
 
     if (argc != 3)
     {
-        usage();
+        usage(whoami);
     }
     try
     {
diff --git a/libqpdf/Pl_DCT.cc b/libqpdf/Pl_DCT.cc
index de7e1a5e..7231486d 100644
--- a/libqpdf/Pl_DCT.cc
+++ b/libqpdf/Pl_DCT.cc
@@ -302,8 +302,9 @@ Pl_DCT::compress(void* cinfo_p, Buffer* b)
     unsigned int width = cinfo->image_width *
         QIntC::to_uint(cinfo->input_components);
     size_t expected_size =
-        cinfo->image_height * cinfo->image_width *
-        QIntC::to_uint(cinfo->input_components);
+        QIntC::to_size(cinfo->image_height) *
+        QIntC::to_size(cinfo->image_width) *
+        QIntC::to_size(cinfo->input_components);
     if (b->getSize() != expected_size)
     {
         throw std::runtime_error(
diff --git a/libqpdf/QPDFObjectHandle.cc b/libqpdf/QPDFObjectHandle.cc
index ab77fb73..85493680 100644
--- a/libqpdf/QPDFObjectHandle.cc
+++ b/libqpdf/QPDFObjectHandle.cc
@@ -1607,12 +1607,12 @@ QPDFObjectHandle::pipeContentStreams(
         std::string og =
             QUtil::int_to_string(stream.getObjectID()) + " " +
             QUtil::int_to_string(stream.getGeneration());
-        std::string description = "content stream object " + og;
+        std::string w_description = "content stream object " + og;
         if (! stream.pipeStreamData(p, 0, qpdf_dl_specialized))
         {
             QTC::TC("qpdf", "QPDFObjectHandle errors in parsecontent");
             throw QPDFExc(qpdf_e_damaged_pdf, "content stream",
-                          description, 0,
+                          w_description, 0,
                           "errors while decoding content stream");
         }
     }
@@ -1685,13 +1685,13 @@ QPDFObjectHandle::parseContentStream_data(
     ParserCallbacks* callbacks,
     QPDF* context)
 {
-    size_t length = stream_data->getSize();
+    size_t stream_length = stream_data->getSize();
     PointerHolder<InputSource> input =
         new BufferInputSource(description, stream_data.getPointer());
     QPDFTokenizer tokenizer;
     tokenizer.allowEOF();
     bool empty = false;
-    while (QIntC::to_size(input->tell()) < length)
+    while (QIntC::to_size(input->tell()) < stream_length)
     {
         // Read a token and seek to the beginning. The offset we get
         // from this process is the beginning of the next
diff --git a/libqpdf/QPDFPageObjectHelper.cc b/libqpdf/QPDFPageObjectHelper.cc
index 8e0aac06..b7da816e 100644
--- a/libqpdf/QPDFPageObjectHelper.cc
+++ b/libqpdf/QPDFPageObjectHelper.cc
@@ -76,10 +76,8 @@ InlineImageTracker::convertIIDict(QPDFObjectHandle odict)
     dict.replaceKey("/Type", QPDFObjectHandle::newName("/XObject"));
     dict.replaceKey("/Subtype", QPDFObjectHandle::newName("/Image"));
     std::set<std::string> keys = odict.getKeys();
-    for (std::set<std::string>::iterator iter = keys.begin();
-         iter != keys.end(); ++iter)
+    for (auto key: keys)
     {
-        std::string key = *iter;
         QPDFObjectHandle value = odict.getKey(key);
         if (key == "/BPC")
         {
@@ -176,14 +174,12 @@ InlineImageTracker::convertIIDict(QPDFObjectHandle odict)
             {
                 filters = value.getArrayAsVector();
             }
-            for (std::vector<QPDFObjectHandle>::iterator iter =
-                     filters.begin();
-                 iter != filters.end(); ++iter)
+            for (auto& iter: filters)
             {
                 std::string name;
-                if ((*iter).isName())
+                if (iter.isName())
                 {
-                    name = (*iter).getName();
+                    name = iter.getName();
                 }
                 if (name == "/AHx")
                 {
@@ -219,7 +215,7 @@ InlineImageTracker::convertIIDict(QPDFObjectHandle odict)
                 }
                 if (! name.empty())
                 {
-                    *iter = QPDFObjectHandle::newName(name);
+                    iter = QPDFObjectHandle::newName(name);
                 }
             }
             if (value.isName() && (filters.size() == 1))
diff --git a/libqpdf/QPDFTokenizer.cc b/libqpdf/QPDFTokenizer.cc
index 207d62d8..4217575c 100644
--- a/libqpdf/QPDFTokenizer.cc
+++ b/libqpdf/QPDFTokenizer.cc
@@ -175,8 +175,8 @@ QPDFTokenizer::resolveLiteral()
                     num[0] = this->m->val.at(i+1);
                     num[1] = this->m->val.at(i+2);
                     num[2] = '\0';
-                    char ch = static_cast<char>(strtol(num, 0, 16));
-                    if (ch == '\0')
+                    char ch2 = static_cast<char>(strtol(num, 0, 16));
+                    if (ch2 == '\0')
                     {
                         this->m->type = tt_bad;
                         QTC::TC("qpdf", "QPDFTokenizer null in name");
@@ -186,7 +186,7 @@ QPDFTokenizer::resolveLiteral()
                     }
                     else
                     {
-                        nval.append(1, ch);
+                        nval.append(1, ch2);
                     }
                     i += 2;
                 }
@@ -719,7 +719,7 @@ QPDFTokenizer::findEI(PointerHolder<InputSource> input)
                 for (std::string::iterator iter = value.begin();
                      iter != value.end(); ++iter)
                 {
-                    char ch = *iter;
+                    signed char ch = *iter;
                     if (((ch >= 'a') && (ch <= 'z')) ||
                         ((ch >= 'A') && (ch <= 'Z')) ||
                         (ch == '*'))
@@ -729,8 +729,10 @@ QPDFTokenizer::findEI(PointerHolder<InputSource> input)
                         // alphabetic characters.
                         found_alpha = true;
                     }
-                    else if (((ch < 32) && (! isSpace(ch))) || (ch > 127))
+                    else if ((ch < 32) && (! isSpace(ch)))
                     {
+                        // ch is signed, so characters outside of
+                        // 7-bit will be < 0.
                         found_non_printable = true;
                         break;
                     }
diff --git a/libqpdf/QPDFWriter.cc b/libqpdf/QPDFWriter.cc
index cdab9db1..15999436 100644
--- a/libqpdf/QPDFWriter.cc
+++ b/libqpdf/QPDFWriter.cc
@@ -1790,14 +1790,14 @@ QPDFWriter::unparseObject(QPDFObjectHandle object, int level,
 	    }
 	}
 	bool normalize = false;
-	bool compress = false;
+	bool compress_stream = false;
         bool uncompress = false;
 	if (is_metadata &&
 	    ((! this->m->encrypted) || (this->m->encrypt_metadata == false)))
 	{
 	    QTC::TC("qpdf", "QPDFWriter not compressing metadata");
 	    filter = true;
-	    compress = false;
+	    compress_stream = false;
             uncompress = true;
 	}
 	else if (this->m->normalize_content &&
@@ -1808,7 +1808,7 @@ QPDFWriter::unparseObject(QPDFObjectHandle object, int level,
 	}
 	else if (filter && this->m->compress_streams)
 	{
-	    compress = true;
+	    compress_stream = true;
 	    QTC::TC("qpdf", "QPDFWriter compressing uncompressed stream");
 	}
 
@@ -1825,7 +1825,7 @@ QPDFWriter::unparseObject(QPDFObjectHandle object, int level,
                 object.pipeStreamData(
                     this->m->pipeline,
                     (((filter && normalize) ? qpdf_ef_normalize : 0) |
-                     ((filter && compress) ? qpdf_ef_compress : 0)),
+                     ((filter && compress_stream) ? qpdf_ef_compress : 0)),
                     (filter
                      ? (uncompress ? qpdf_dl_all : this->m->stream_decode_level)
                      : qpdf_dl_none), false, (attempt == 1));
@@ -1845,7 +1845,7 @@ QPDFWriter::unparseObject(QPDFObjectHandle object, int level,
 	}
 	else
 	{
-	    compress = false;
+	    compress_stream = false;
 	}
 
 	this->m->cur_stream_length = stream_data->getSize();
@@ -1856,7 +1856,7 @@ QPDFWriter::unparseObject(QPDFObjectHandle object, int level,
 	}
 	adjustAESStreamLength(this->m->cur_stream_length);
 	unparseObject(stream_dict, 0, flags,
-                      this->m->cur_stream_length, compress);
+                      this->m->cur_stream_length, compress_stream);
 	unsigned char last_char = '\0';
 	writeString("\nstream\n");
         {
@@ -2330,11 +2330,10 @@ QPDFWriter::initializeSpecialStreams()
 	    contents_objects.push_back(contents.getObjGen());
 	}
 
-	for (std::vector<QPDFObjGen>::iterator iter = contents_objects.begin();
-	     iter != contents_objects.end(); ++iter)
+	for (auto const& c: contents_objects)
 	{
-	    this->m->contents_to_page_seq[*iter] = num;
-	    this->m->normalized_streams.insert(*iter);
+	    this->m->contents_to_page_seq[c] = num;
+	    this->m->normalized_streams.insert(c);
 	}
     }
 }
@@ -3462,9 +3461,9 @@ QPDFWriter::writeLinearized()
 	    else
 	    {
 		// Make the file size the same.
-		qpdf_offset_t pos = this->m->pipeline->getCount();
 		writePad(
-                    QIntC::to_int(second_xref_end + hint_length - 1 - pos));
+                    QIntC::to_int(second_xref_end + hint_length -
+                                  1 - this->m->pipeline->getCount()));
 		writeString("\n");
 
 		// If this assertion fails, maybe we didn't have
@@ -3507,7 +3506,7 @@ QPDFWriter::writeLinearized()
 
 	    // Save hint offset since it will be set to zero by
 	    // calling openObject.
-	    qpdf_offset_t hint_offset = this->m->xref[hint_id].getOffset();
+	    qpdf_offset_t hint_offset1 = this->m->xref[hint_id].getOffset();
 
 	    // Write hint stream to a buffer
             {
@@ -3519,12 +3518,12 @@ QPDFWriter::writeLinearized()
 	    hint_length = QIntC::to_offset(hint_buffer->getSize());
 
 	    // Restore hint offset
-	    this->m->xref[hint_id] = QPDFXRefEntry(1, hint_offset, 0);
+	    this->m->xref[hint_id] = QPDFXRefEntry(1, hint_offset1, 0);
             if (lin_pass1_file)
             {
                 // Write some debugging information
                 fprintf(lin_pass1_file, "%% hint_offset=%s\n",
-                        QUtil::int_to_string(hint_offset).c_str());
+                        QUtil::int_to_string(hint_offset1).c_str());
                 fprintf(lin_pass1_file, "%% hint_length=%s\n",
                         QUtil::int_to_string(hint_length).c_str());
                 fprintf(lin_pass1_file, "%% second_xref_offset=%s\n",
diff --git a/libqpdf/QPDF_Stream.cc b/libqpdf/QPDF_Stream.cc
index 37ff9417..e4a3c039 100644
--- a/libqpdf/QPDF_Stream.cc
+++ b/libqpdf/QPDF_Stream.cc
@@ -555,12 +555,14 @@ QPDF_Stream::pipeStreamData(Pipeline* pipeline, bool* filterp,
             to_delete.push_back(pipeline);
         }
 
-	for (std::vector<std::string>::reverse_iterator iter = filters.rbegin();
-	     iter != filters.rend(); ++iter)
+	for (std::vector<std::string>::reverse_iterator f_iter =
+                 filters.rbegin();
+	     f_iter != filters.rend(); ++f_iter)
 	{
-	    std::string const& filter = *iter;
+	    std::string const& filter_name = *f_iter;
 
-            if ((filter == "/FlateDecode") || (filter == "/LZWDecode"))
+            if ((filter_name == "/FlateDecode") ||
+                (filter_name == "/LZWDecode"))
             {
                 if ((predictor >= 10) && (predictor <= 15))
                 {
@@ -584,39 +586,39 @@ QPDF_Stream::pipeStreamData(Pipeline* pipeline, bool* filterp,
                 }
             }
 
-	    if (filter == "/Crypt")
+	    if (filter_name == "/Crypt")
 	    {
 		// Ignore -- handled by pipeStreamData
 	    }
-	    else if (filter == "/FlateDecode")
+	    else if (filter_name == "/FlateDecode")
 	    {
 		pipeline = new Pl_Flate("stream inflate",
 					pipeline, Pl_Flate::a_inflate);
 		to_delete.push_back(pipeline);
 	    }
-	    else if (filter == "/ASCII85Decode")
+	    else if (filter_name == "/ASCII85Decode")
 	    {
 		pipeline = new Pl_ASCII85Decoder("ascii85 decode", pipeline);
 		to_delete.push_back(pipeline);
 	    }
-	    else if (filter == "/ASCIIHexDecode")
+	    else if (filter_name == "/ASCIIHexDecode")
 	    {
 		pipeline = new Pl_ASCIIHexDecoder("asciiHex decode", pipeline);
 		to_delete.push_back(pipeline);
 	    }
-	    else if (filter == "/LZWDecode")
+	    else if (filter_name == "/LZWDecode")
 	    {
 		pipeline = new Pl_LZWDecoder("lzw decode", pipeline,
 					     early_code_change);
 		to_delete.push_back(pipeline);
 	    }
-	    else if (filter == "/RunLengthDecode")
+	    else if (filter_name == "/RunLengthDecode")
 	    {
 		pipeline = new Pl_RunLength("runlength decode", pipeline,
                                             Pl_RunLength::a_decode);
 		to_delete.push_back(pipeline);
 	    }
-	    else if (filter == "/DCTDecode")
+	    else if (filter_name == "/DCTDecode")
 	    {
 		pipeline = new Pl_DCT("DCT decode", pipeline);
 		to_delete.push_back(pipeline);
diff --git a/libqpdf/QPDF_encryption.cc b/libqpdf/QPDF_encryption.cc
index 9880face..48351122 100644
--- a/libqpdf/QPDF_encryption.cc
+++ b/libqpdf/QPDF_encryption.cc
@@ -322,10 +322,10 @@ hash_V5(std::string const& password,
             int next_hash = ((E_mod_3 == 0) ? 256 :
                              (E_mod_3 == 1) ? 384 :
                              512);
-            Pl_SHA2 hash(next_hash);
-            hash.write(QUtil::unsigned_char_pointer(E), E.length());
-            hash.finish();
-            K = hash.getRawDigest();
+            Pl_SHA2 sha2(next_hash);
+            sha2.write(QUtil::unsigned_char_pointer(E), E.length());
+            sha2.finish();
+            K = sha2.getRawDigest();
 
             if (round_number >= 64)
             {
diff --git a/libqpdf/QPDF_linearization.cc b/libqpdf/QPDF_linearization.cc
index 763b8ee0..3dff1c17 100644
--- a/libqpdf/QPDF_linearization.cc
+++ b/libqpdf/QPDF_linearization.cc
@@ -374,9 +374,9 @@ QPDF::readHintStream(Pipeline& pl, qpdf_offset_t offset, size_t length)
 	QTC::TC("qpdf", "QPDF hint table length indirect");
 	// Force resolution
 	(void) length_obj.getIntValue();
-	ObjCache& oc = this->m->obj_cache[length_obj.getObjGen()];
-	min_end_offset = oc.end_before_space;
-	max_end_offset = oc.end_after_space;
+	ObjCache& oc2 = this->m->obj_cache[length_obj.getObjGen()];
+	min_end_offset = oc2.end_before_space;
+	max_end_offset = oc2.end_after_space;
     }
     else
     {
diff --git a/libqpdf/QUtil.cc b/libqpdf/QUtil.cc
index c3c4f12f..072a939c 100644
--- a/libqpdf/QUtil.cc
+++ b/libqpdf/QUtil.cc
@@ -812,7 +812,7 @@ QUtil::toUTF8(unsigned long uval)
 	// maximum value that will fit in the current number of bytes
 	unsigned char maxval = 0x3f; // six bits
 
-	while (uval > maxval)
+	while (uval > QIntC::to_ulong(maxval))
 	{
 	    // Assign low six bits plus 10000000 to lowest unused
 	    // byte position, then shift
@@ -2163,12 +2163,12 @@ QUtil::win_ansi_to_utf8(std::string const& val)
     for (unsigned int i = 0; i < len; ++i)
     {
         unsigned char ch = static_cast<unsigned char>(val.at(i));
-        unsigned short val = ch;
+        unsigned short ch_short = ch;
         if ((ch >= 128) && (ch <= 160))
         {
-            val = win_ansi_to_unicode[ch - 128];
+            ch_short = win_ansi_to_unicode[ch - 128];
         }
-        result += QUtil::toUTF8(val);
+        result += QUtil::toUTF8(ch_short);
     }
     return result;
 }
@@ -2181,12 +2181,12 @@ QUtil::mac_roman_to_utf8(std::string const& val)
     for (unsigned int i = 0; i < len; ++i)
     {
         unsigned char ch = static_cast<unsigned char>(val.at(i));
-        unsigned short val = ch;
+        unsigned short ch_short = ch;
         if (ch >= 128)
         {
-            val = mac_roman_to_unicode[ch - 128];
+            ch_short = mac_roman_to_unicode[ch - 128];
         }
-        result += QUtil::toUTF8(val);
+        result += QUtil::toUTF8(ch_short);
     }
     return result;
 }
@@ -2199,12 +2199,12 @@ QUtil::pdf_doc_to_utf8(std::string const& val)
     for (unsigned int i = 0; i < len; ++i)
     {
         unsigned char ch = static_cast<unsigned char>(val.at(i));
-        unsigned short val = ch;
+        unsigned short ch_short = ch;
         if ((ch >= 128) && (ch <= 160))
         {
-            val = pdf_doc_to_unicode[ch - 128];
+            ch_short = pdf_doc_to_unicode[ch - 128];
         }
-        result += QUtil::toUTF8(val);
+        result += QUtil::toUTF8(ch_short);
     }
     return result;
 }
diff --git a/qpdf/qpdf.cc b/qpdf/qpdf.cc
index 02a95c73..b685d2e5 100644
--- a/qpdf/qpdf.cc
+++ b/qpdf/qpdf.cc
@@ -3610,13 +3610,10 @@ static void do_show_pages(QPDF& pdf, Options& o)
             if (! images.empty())
             {
                 std::cout << "  images:" << std::endl;
-                for (std::map<std::string,
-                         QPDFObjectHandle>::iterator
-                         iter = images.begin();
-                     iter != images.end(); ++iter)
+                for (auto const& iter2: images)
                 {
-                    std::string const& name = (*iter).first;
-                    QPDFObjectHandle image = (*iter).second;
+                    std::string const& name = iter2.first;
+                    QPDFObjectHandle image = iter2.second;
                     QPDFObjectHandle dict = image.getDict();
                     int width =
                         dict.getKey("/Width").getIntValueAsInt();
@@ -3633,11 +3630,9 @@ static void do_show_pages(QPDF& pdf, Options& o)
         std::cout << "  content:" << std::endl;
         std::vector<QPDFObjectHandle> content =
             ph.getPageContents();
-        for (std::vector<QPDFObjectHandle>::iterator iter =
-                 content.begin();
-             iter != content.end(); ++iter)
+        for (auto& iter2: content)
         {
-            std::cout << "    " << (*iter).unparse() << std::endl;
+            std::cout << "    " << iter2.unparse() << std::endl;
         }
     }
 }
@@ -3738,14 +3733,12 @@ static void do_json_pages(QPDF& pdf, Options& o, JSON& j)
             "images", JSON::makeArray());
         std::map<std::string, QPDFObjectHandle> images =
             ph.getPageImages();
-        for (std::map<std::string, QPDFObjectHandle>::iterator iter =
-                 images.begin();
-             iter != images.end(); ++iter)
+        for (auto const& iter2: images)
         {
             JSON j_image = j_images.addArrayElement(JSON::makeDictionary());
             j_image.addDictionaryMember(
-                "name", JSON::makeString((*iter).first));
-            QPDFObjectHandle image = (*iter).second;
+                "name", JSON::makeString(iter2.first));
+            QPDFObjectHandle image = iter2.second;
             QPDFObjectHandle dict = image.getDict();
             j_image.addDictionaryMember("object", image.getJSON());
             j_image.addDictionaryMember(
@@ -3783,10 +3776,9 @@ static void do_json_pages(QPDF& pdf, Options& o, JSON& j)
         JSON j_contents = j_page.addDictionaryMember(
             "contents", JSON::makeArray());
         std::vector<QPDFObjectHandle> content = ph.getPageContents();
-        for (std::vector<QPDFObjectHandle>::iterator iter = content.begin();
-             iter != content.end(); ++iter)
+        for (auto& iter2: content)
         {
-            j_contents.addArrayElement((*iter).getJSON());
+            j_contents.addArrayElement(iter2.getJSON());
         }
         j_page.addDictionaryMember(
             "label", pldh.getLabelForPage(pageno).getJSON());
@@ -4761,12 +4753,10 @@ static void handle_transformations(QPDF& pdf, Options& o)
             QPDFObjectHandle page = ph.getObjectHandle();
             std::map<std::string, QPDFObjectHandle> images =
                 ph.getPageImages();
-            for (std::map<std::string, QPDFObjectHandle>::iterator iter =
-                     images.begin();
-                 iter != images.end(); ++iter)
+            for (auto& iter2: images)
             {
-                std::string name = (*iter).first;
-                QPDFObjectHandle& image = (*iter).second;
+                std::string name = iter2.first;
+                QPDFObjectHandle& image = iter2.second;
                 ImageOptimizer* io = new ImageOptimizer(o, image);
                 PointerHolder<QPDFObjectHandle::StreamDataProvider> sdp(io);
                 if (io->evaluate("image " + name + " on page " +
diff --git a/qpdf/test_driver.cc b/qpdf/test_driver.cc
index 74aa7c26..07445dea 100644
--- a/qpdf/test_driver.cc
+++ b/qpdf/test_driver.cc
@@ -347,10 +347,10 @@ void runtest(int n, char const* filename1, char const* arg2)
 	else if (qtest.isArray())
 	{
 	    QTC::TC("qpdf", "main QTest array");
-	    int n = qtest.getArrayNItems();
+	    int nitems = qtest.getArrayNItems();
 	    std::cout << "/QTest is an array with "
-		      << n << " items" << std::endl;
-	    for (int i = 0; i < n; ++i)
+		      << nitems << " items" << std::endl;
+	    for (int i = 0; i < nitems; ++i)
 	    {
 		QTC::TC("qpdf", "main QTest array indirect",
 			qtest.getArrayItem(i).isIndirect() ? 1 : 0);
@@ -510,11 +510,10 @@ void runtest(int n, char const* filename1, char const* arg2)
 	    std::cout << "  images:" << std::endl;
 	    std::map<std::string, QPDFObjectHandle> images =
 		page.getPageImages();
-	    for (std::map<std::string, QPDFObjectHandle>::iterator iter =
-		     images.begin(); iter != images.end(); ++iter)
+	    for (auto const& iter2: images)
 	    {
-		std::string const& name = (*iter).first;
-		QPDFObjectHandle image = (*iter).second;
+		std::string const& name = iter2.first;
+		QPDFObjectHandle image = iter2.second;
 		QPDFObjectHandle dict = image.getDict();
 		long long width = dict.getKey("/Width").getIntValue();
 		long long height = dict.getKey("/Height").getIntValue();
@@ -525,10 +524,9 @@ void runtest(int n, char const* filename1, char const* arg2)
 
 	    std::cout << "  content:" << std::endl;
 	    std::vector<QPDFObjectHandle> content = page.getPageContents();
-	    for (std::vector<QPDFObjectHandle>::iterator iter = content.begin();
-		 iter != content.end(); ++iter)
+	    for (auto& iter2: content)
 	    {
-		std::cout << "    " << (*iter).unparse() << std::endl;
+		std::cout << "    " << iter2.unparse() << std::endl;
 	    }
 
 	    std::cout << "end page " << pageno << std::endl;
@@ -539,8 +537,8 @@ void runtest(int n, char const* filename1, char const* arg2)
 	if (qstrings.isArray())
 	{
 	    std::cout << "QStrings:" << std::endl;
-	    int n = qstrings.getArrayNItems();
-	    for (int i = 0; i < n; ++i)
+	    int nitems = qstrings.getArrayNItems();
+	    for (int i = 0; i < nitems; ++i)
 	    {
 		std::cout << qstrings.getArrayItem(i).getUTF8Value()
 			  << std::endl;
@@ -551,8 +549,8 @@ void runtest(int n, char const* filename1, char const* arg2)
 	if (qnumbers.isArray())
 	{
 	    std::cout << "QNumbers:" << std::endl;
-	    int n = qnumbers.getArrayNItems();
-	    for (int i = 0; i < n; ++i)
+	    int nitems = qnumbers.getArrayNItems();
+	    for (int i = 0; i < nitems; ++i)
 	    {
 		std::cout << QUtil::double_to_string(
 		    qnumbers.getArrayItem(i).getNumericValue(), 3)
@@ -1853,8 +1851,8 @@ void runtest(int n, char const* filename1, char const* arg2)
         // button-set*.pdf are designed for this test case.
         QPDFObjectHandle acroform = pdf.getRoot().getKey("/AcroForm");
         QPDFObjectHandle fields = acroform.getKey("/Fields");
-        int n = fields.getArrayNItems();
-        for (int i = 0; i < n; ++i)
+        int nitems = fields.getArrayNItems();
+        for (int i = 0; i < nitems; ++i)
         {
             QPDFObjectHandle field = fields.getArrayItem(i);
             QPDFObjectHandle T = field.getKey("/T");
@@ -1900,8 +1898,8 @@ void runtest(int n, char const* filename1, char const* arg2)
         // generating testing.
         QPDFObjectHandle acroform = pdf.getRoot().getKey("/AcroForm");
         QPDFObjectHandle fields = acroform.getKey("/Fields");
-        int n = fields.getArrayNItems();
-        for (int i = 0; i < n; ++i)
+        int nitems = fields.getArrayNItems();
+        for (int i = 0; i < nitems; ++i)
         {
             QPDFObjectHandle field = fields.getArrayItem(i);
             QPDFObjectHandle T = field.getKey("/T");