[lldb] Fix string summary of an empty NSPathStore2

[teemperor]

Summary

Printing a summary for an empty NSPathStore2 string currently prints random bytes behind the empty string pointer from memory (rdar://55575888).

It seems the reason for this is that the SourceSize parameter in the ReadStringAndDumpToStreamOptions - which is supposed to contain the string
length - actually uses the length 0 as a magic value for saying "read as much as possible from the buffer" which is clearly wrong for empty strings.

This patch adds another flag that indicates if we have know the string length or not and makes this behaviour dependent on that (which seemingly
was the original purpose of this magic value).

[teemperor]

• Land the NFC test additions to other string classes as separate NFC commits.
• Rebase on the already landed refactoring.

[aprantl]

lldb/include/lldb/DataFormatters/StringPrinter.h

181

I don't know the LLDB rules that well: is the convention really GetHas instead of Has?

lldb/source/DataFormatters/StringPrinter.cpp

546

why unconditionally call GetSourceSize? Should we move it into the else?

563

Why call GetBytes() if sourceSize is 0? Should we reverse the two conditions?

[teemperor]

• GetHasSourceSize -> HasSourceSize
• Moved some code around according to feedback.

[shafik]

lldb/source/DataFormatters/StringPrinter.cpp

544

Why not just make this uint32_t making this auto gains us nothing but now I am left wondering do the types match later on when we use max_size.

[teemperor]

• Rebased the patch.

This has been (really) delayed because of the whole unit test I wanted to write, but I'll just land this as-is (as having this broken even longer just because I haven't written that new unit test seems silly).

lldb/include/lldb/DataFormatters/StringPrinter.h

public:
 
     ReadStringAndDumpToStreamOptions &SetSourceSize(uint32_t s) {
       m_source_size = s;
       return *this;
     }
 
     uint32_t GetSourceSize() const { return m_source_size; }
 
+    ReadStringAndDumpToStreamOptions &SetHasSourceSize(bool e) {
+      m_has_source_size = e;
+      return *this;
+    }
+
+    bool GetHasSourceSize() const { return m_has_source_size; }
+
     ReadStringAndDumpToStreamOptions &SetNeedsZeroTermination(bool z) {
       m_needs_zero_termination = z;
       return *this;
     }
 
     bool GetNeedsZeroTermination() const { return m_needs_zero_termination; }
 
     ReadStringAndDumpToStreamOptions &SetBinaryZeroIsTerminator(bool e) {
public:
   private:
     uint64_t m_location = 0;
     lldb::ProcessSP m_process_sp;
     Stream *m_stream = nullptr;
     std::string m_prefix_token;
     std::string m_suffix_token;
     char m_quote = '"';
     uint32_t m_source_size = 0;
+    /// True if we know the source size of the string.
+    bool m_has_source_size = false;
     bool m_needs_zero_termination = true;
     bool m_escape_non_printables = true;
     bool m_ignore_max_length = false;
     bool m_zero_is_terminator = true;
     lldb::LanguageType m_language_type = lldb::eLanguageTypeUnknown;
   };
 
   class ReadBufferAndDumpToStreamOptions {
public:
 
     ReadBufferAndDumpToStreamOptions &SetStream(Stream *s) {
       m_stream = s;
       return *this;
     }
 
     Stream *GetStream() const { return m_stream; }
 
     ReadBufferAndDumpToStreamOptions &SetPrefixToken(const std::string &p) {
       m_prefix_token = p;
       return *this;
     }
 
     ReadBufferAndDumpToStreamOptions &SetPrefixToken(std::nullptr_t) {
       m_prefix_token.clear();
       return *this;
     }

lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/nsstring/TestDataFormatterNSString.py

def rdar11106605_commands(self):
         self.expect('frame variable french', substrs=[
                     'Que veut cette horde d\'esclaves, De traîtres, de rois conjurés?'])
         self.expect('frame variable german', substrs=[
                     'Über-Ich und aus den Ansprüchen der sozialen Umwelt'])
         self.expect('frame variable japanese', substrs=['色は匂へど散りぬるを'])
         self.expect('frame variable hebrew', substrs=['לילה טוב'])
 
     def nsstring_data_formatter_commands(self):
-        self.expect('frame variable str0 str1 str2 str3 str4 str5 str6 str8 str9 str10 str11 label1 label2 processName str12',
-                    substrs=['(NSString *) str1 = ', ' @"A rather short ASCII NSString object is here"',
+        self.expect('frame variable empty str0 str1 str2 str3 str4 str5 str6 str8 str9 str10 str11 label1 label2 processName str12',
+                    substrs=['(NSString *) empty = ', ' @""',
+                             '(NSString *) str1 = ', ' @"A rather short ASCII NSString object is here"',
                              # '(NSString *) str0 = ',' @"255"',
                              '(NSString *) str1 = ', ' @"A rather short ASCII NSString object is here"',
                              '(NSString *) str2 = ', ' @"A rather short UTF8 NSString object is here"',
                              '(NSString *) str3 = ', ' @"A string made with the at sign is here"',
                              '(NSString *) str4 = ', ' @"This is string number 4 right here"',
                              '(NSString *) str5 = ', ' @"{{1, 1}, {5, 5}}"',
                              '(NSString *) str6 = ', ' @"1ST"',
                              '(NSString *) str8 = ', ' @"hasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTimehasVeryLongExtensionThisTime',
def nsstring_data_formatter_commands(self):
                 ' @"hello world from foo"',
                 '(NSAttributedString *) mutableAttrString = ',
                 ' @"hello world from foo"',
                 '(NSString *) mutableGetConst = ',
                 ' @"foo said this string needs to be very long so much longer than whatever other string has been seen ever before by anyone of the mankind that of course this is still not long enough given what foo our friend foo our lovely dearly friend foo desired of us so i am adding more stuff here for the sake of it and for the joy of our friend who is named guess what just foo. hence, dear friend foo, stay safe, your string is now  long enough to accommodate your testing need and I will make sure that if not we extend it with even more fuzzy random meaningless words pasted one after the other from a long tiresome friday evening spent working in my office. my office mate went home but I am still randomly typing just for the fun of seeing what happens of the length of a Mutable String in Cocoa if it goes beyond one byte.. so be it, dear foo"'])
 
         self.expect('expr -d run-target -- path', substrs=['usr/blah/stuff'])
         self.expect('frame variable path', substrs=['usr/blah/stuff'])
+        self.expect('expr -d run-target -- empty_path', substrs=['@""'])
+        self.expect('frame variable empty_path', substrs=['@""'])
 
     def nsstring_withNULs_commands(self):
         """Check that the NSString formatter supports embedded NULs in the text"""
         self.expect(
             'po strwithNULs',
             substrs=['a very much boring task to write'])
         self.expect('expr [strwithNULs length]', substrs=['54'])
         self.expect('frame variable strwithNULs', substrs=[
                     '@"a very much boring task to write\\0a string this way!!'])
         self.expect('po strwithNULs2', substrs=[
                     'a very much boring task to write'])
         self.expect('expr [strwithNULs2 length]', substrs=['52'])
         self.expect('frame variable strwithNULs2', substrs=[
                     '@"a very much boring task to write\\0a string this way!!'])

lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-objc/nsstring/main.m

 #else
 #import <Carbon/Carbon.h>
 #endif
 
 int main (int argc, const char * argv[])
 {
     
     NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
-
+      NSString *empty = @"";
       NSString *str0 = [[NSNumber numberWithUnsignedLongLong:0xFF] stringValue];
       NSString *str1 = [NSString stringWithCString:"A rather short ASCII NSString object is here" encoding:NSASCIIStringEncoding];
       NSString *str2 = [NSString stringWithUTF8String:"A rather short UTF8 NSString object is here"];
       NSString *str3 = @"A string made with the at sign is here";
       NSString *str4 = [NSString stringWithFormat:@"This is string number %ld right here", (long)4];
       NSRect ns_rect_4str = {{1,1},{5,5}};
       NSString* str5 = NSStringFromRect(ns_rect_4str);
       NSString* str6 = [@"/usr/doc/README.1ST" pathExtension];
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
 
       [mutableGetConst length];
       CFMutableStringRef mutable_string_ref = CFStringCreateMutable(NULL,100);
       CFStringAppend(mutable_string_ref, CFSTR("Wish ya knew"));
       CFStringRef cfstring_ref = CFSTR("HELLO WORLD");
 
   NSArray *components = @[@"usr", @"blah", @"stuff"];
   NSString *path = [NSString pathWithComponents: components];
+  NSString *empty_path = [empty stringByDeletingPathExtension];
 
   const unichar someOfTheseAreNUL[] = {'a',' ', 'v','e','r','y',' ',
       'm','u','c','h',' ','b','o','r','i','n','g',' ','t','a','s','k',
       ' ','t','o',' ','w','r','i','t','e', 0, 'a', ' ', 's', 't', 'r', 'i', 'n', 'g', ' ',
       't','h','i','s',' ','w','a','y','!','!', 0x03C3, 0};
   NSString *strwithNULs = [NSString stringWithCharacters: someOfTheseAreNUL
                                            length: sizeof someOfTheseAreNUL / sizeof *someOfTheseAreNUL];
 

lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-stl/libcxx/string/TestDataFormatterLibcxxString.py

def test_with_run_command(self):
 
         # Execute the cleanup function during test case tear down.
         self.addTearDownHook(cleanup)
 
         ns = self.namespace
         self.expect(
             "frame variable",
             substrs=[
+                '(%s::wstring) wempty = L""'%ns,
                 '(%s::wstring) s = L"hello world! מזל טוב!"'%ns,
                 '(%s::wstring) S = L"!!!!"'%ns,
                 '(const wchar_t *) mazeltov = 0x',
                 'L"מזל טוב"',
+                '(%s::string) empty = ""'%ns,
                 '(%s::string) q = "hello world"'%ns,
                 '(%s::string) Q = "quite a long std::strin with lots of info inside it"'%ns,
                 '(%s::string) IHaveEmbeddedZeros = "a\\0b\\0c\\0d"'%ns,
                 '(%s::wstring) IHaveEmbeddedZerosToo = L"hello world!\\0てざ ル゜䋨ミ㠧槊 きゅへ狦穤襩 じゃ馩リョ 䤦監"'%ns,
                 '(%s::u16string) u16_string = u"ß水氶"'%ns,
-                '(%s::u32string) u32_string = U"🍄🍅🍆🍌"'%ns])
+                # FIXME: This should have a 'u' prefix.
+                '(%s::u16string) u16_empty = ""'%ns,
+                '(%s::u32string) u32_string = U"🍄🍅🍆🍌"'%ns,
+                # FIXME: This should have a 'U' prefix.
+                '(%s::u32string) u32_empty = ""'%ns
+])
 
         self.runCmd("n")
 
         TheVeryLongOne = self.frame().FindVariable("TheVeryLongOne")
         summaryOptions = lldb.SBTypeSummaryOptions()
         summaryOptions.SetCapping(lldb.eTypeSummaryUncapped)
         uncappedSummaryStream = lldb.SBStream()
         TheVeryLongOne.GetSummary(uncappedSummaryStream, summaryOptions)

lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-stl/libcxx/string/main.cpp

 #include <string>
 
 int main()
 {
+    std::wstring wempty(L"");
     std::wstring s(L"hello world! מזל טוב!");
     std::wstring S(L"!!!!");
     const wchar_t *mazeltov = L"מזל טוב";
+    std::string empty("");
     std::string q("hello world");
     std::string Q("quite a long std::strin with lots of info inside it");
     std::string TheVeryLongOne("1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890someText1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890");
     std::string IHaveEmbeddedZeros("a\0b\0c\0d",7);
     std::wstring IHaveEmbeddedZerosToo(L"hello world!\0てざ ル゜䋨ミ㠧槊 きゅへ狦穤襩 じゃ馩リョ 䤦監", 38);
     std::u16string u16_string(u"ß水氶");
+    std::u16string u16_empty(u"");
     std::u32string u32_string(U"🍄🍅🍆🍌");
+    std::u32string u32_empty(U"");
     S.assign(L"!!!!!"); // Set break point at this line.
     return 0;
 }

lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-stl/libstdcpp/string/TestDataFormatterStdString.py

def test_with_run_command(self):
             self.runCmd('type synth clear', check=False)
             self.runCmd(
                 "settings set target.max-children-count 256",
                 check=False)
 
         # Execute the cleanup function during test case tear down.
         self.addTearDownHook(cleanup)
 
+        var_wempty = self.frame().FindVariable('wempty')
         var_s = self.frame().FindVariable('s')
         var_S = self.frame().FindVariable('S')
         var_mazeltov = self.frame().FindVariable('mazeltov')
+        var_empty = self.frame().FindVariable('empty')
         var_q = self.frame().FindVariable('q')
         var_Q = self.frame().FindVariable('Q')
 
+        self.assertTrue(var_wempty.GetSummary() == 'L""', "wempty summary wrong")
         self.assertTrue(
             var_s.GetSummary() == 'L"hello world! מזל טוב!"',
             "s summary wrong")
         self.assertTrue(var_S.GetSummary() == 'L"!!!!"', "S summary wrong")
         self.assertTrue(
             var_mazeltov.GetSummary() == 'L"מזל טוב"',
             "mazeltov summary wrong")
+        self.assertTrue(var_empty.GetSummary() == '""', "empty summary wrong")
         self.assertTrue(
             var_q.GetSummary() == '"hello world"',
             "q summary wrong")
         self.assertTrue(
             var_Q.GetSummary() == '"quite a long std::strin with lots of info inside it"',
             "Q summary wrong")
 
         self.runCmd("next")
 
         self.assertTrue(
             var_S.GetSummary() == 'L"!!!!!"',
             "new S summary wrong")

lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-stl/libstdcpp/string/main.cpp

 #include <string>
 
 int main()
 {
+    std::wstring wempty(L"");
     std::wstring s(L"hello world! מזל טוב!");
     std::wstring S(L"!!!!");
     const wchar_t *mazeltov = L"מזל טוב";
+    std::string empty("");
     std::string q("hello world");
     std::string Q("quite a long std::strin with lots of info inside it");
     S.assign(L"!!!!!"); // Set break point at this line.
     return 0;
 }

lldb/source/DataFormatters/StringPrinter.cpp

static bool ReadUTFBufferAndDumpToStream(
 
   if (!options.GetStream())
     return false;
 
   uint32_t sourceSize = options.GetSourceSize();
   bool needs_zero_terminator = options.GetNeedsZeroTermination();
 
   bool is_truncated = false;
   const auto max_size = process_sp->GetTarget().GetMaximumSizeOfStringSummary();
 
-  if (!sourceSize) {
+  if (!options.GetHasSourceSize()) {
     sourceSize = max_size;
     needs_zero_terminator = true;
   } else if (!options.GetIgnoreMaxLength()) {
     if (sourceSize > max_size) {
       sourceSize = max_size;
       is_truncated = true;
     }
   }
 
   const int bufferSPSize = sourceSize * type_width;
 
   lldb::DataBufferSP buffer_sp(new DataBufferHeap(bufferSPSize, 0));
 
-  if (!buffer_sp->GetBytes())
+  if (!buffer_sp->GetBytes() && sourceSize != 0)
     return false;
 
   Status error;
   char *buffer = reinterpret_cast<char *>(buffer_sp->GetBytes());
 
   if (needs_zero_terminator)
     process_sp->ReadStringFromMemory(options.GetLocation(), buffer,
                                      bufferSPSize, error, type_width);
   else
     process_sp->ReadMemoryFromInferior(options.GetLocation(),
                                        (char *)buffer_sp->GetBytes(),

lldb/source/Plugins/Language/ObjC/NSString.cpp

if (is_mutable) {
     if (error.Fail())
       return false;
     if (has_explicit_length && is_unicode) {
       options.SetLocation(location);
       options.SetProcessSP(process_sp);
       options.SetStream(&stream);
       options.SetQuote('"');
       options.SetSourceSize(explicit_length);
+      options.SetHasSourceSize(has_explicit_length);
       options.SetNeedsZeroTermination(false);
       options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                  TypeSummaryCapping::eTypeSummaryUncapped);
       options.SetBinaryZeroIsTerminator(false);
       options.SetLanguage(summary_options.GetLanguage());
       return StringPrinter::ReadStringAndDumpToStream<
           StringPrinter::StringElementType::UTF16>(options);
     } else {
       options.SetLocation(location + 1);
       options.SetProcessSP(process_sp);
       options.SetStream(&stream);
       options.SetSourceSize(explicit_length);
+      options.SetHasSourceSize(has_explicit_length);
       options.SetNeedsZeroTermination(false);
       options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                  TypeSummaryCapping::eTypeSummaryUncapped);
       options.SetBinaryZeroIsTerminator(false);
       options.SetLanguage(summary_options.GetLanguage());
       return StringPrinter::ReadStringAndDumpToStream<
           StringPrinter::StringElementType::ASCII>(options);
     }
   } else if (is_inline && has_explicit_length && !is_unicode &&
              !is_path_store && !is_mutable) {
     uint64_t location = 3 * ptr_size + valobj_addr;
 
     options.SetLocation(location);
     options.SetProcessSP(process_sp);
     options.SetStream(&stream);
     options.SetQuote('"');
     options.SetSourceSize(explicit_length);
+    options.SetHasSourceSize(has_explicit_length);
     options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                TypeSummaryCapping::eTypeSummaryUncapped);
     options.SetLanguage(summary_options.GetLanguage());
     return StringPrinter::ReadStringAndDumpToStream<
         StringPrinter::StringElementType::ASCII>(options);
   } else if (is_unicode) {
     uint64_t location = valobj_addr + 2 * ptr_size;
     if (is_inline) {
       if (!has_explicit_length) {
         return false;
       } else
         location += ptr_size;
     } else {
       location = process_sp->ReadPointerFromMemory(location, error);
       if (error.Fail())
         return false;
     }
     options.SetLocation(location);
     options.SetProcessSP(process_sp);
     options.SetStream(&stream);
     options.SetQuote('"');
     options.SetSourceSize(explicit_length);
+    options.SetHasSourceSize(has_explicit_length);
     options.SetNeedsZeroTermination(!has_explicit_length);
     options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                TypeSummaryCapping::eTypeSummaryUncapped);
     options.SetBinaryZeroIsTerminator(!has_explicit_length);
     options.SetLanguage(summary_options.GetLanguage());
     return StringPrinter::ReadStringAndDumpToStream<
         StringPrinter::StringElementType::UTF16>(options);
   } else if (is_path_store) {
     ProcessStructReader reader(valobj.GetProcessSP().get(),
                                valobj.GetValueAsUnsigned(0),
                                GetNSPathStore2Type(*valobj.GetTargetSP()));
     explicit_length =
         reader.GetField<uint32_t>(ConstString("lengthAndRef")) >> 20;
     lldb::addr_t location = valobj.GetValueAsUnsigned(0) + ptr_size + 4;
 
     options.SetLocation(location);
     options.SetProcessSP(process_sp);
     options.SetStream(&stream);
     options.SetQuote('"');
     options.SetSourceSize(explicit_length);
+    options.SetHasSourceSize(has_explicit_length);
     options.SetNeedsZeroTermination(!has_explicit_length);
     options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                TypeSummaryCapping::eTypeSummaryUncapped);
     options.SetBinaryZeroIsTerminator(!has_explicit_length);
     options.SetLanguage(summary_options.GetLanguage());
     return StringPrinter::ReadStringAndDumpToStream<
         StringPrinter::StringElementType::UTF16>(options);
   } else if (is_inline) {
     uint64_t location = valobj_addr + 2 * ptr_size;
     if (!has_explicit_length) {
       // in this kind of string, the byte before the string content is a length
       // byte so let's try and use it to handle the embedded NUL case
       Status error;
       explicit_length =
           process_sp->ReadUnsignedIntegerFromMemory(location, 1, 0, error);
       has_explicit_length = !(error.Fail() || explicit_length == 0);
       location++;
     }
     options.SetLocation(location);
     options.SetProcessSP(process_sp);
     options.SetStream(&stream);
     options.SetSourceSize(explicit_length);
+    options.SetHasSourceSize(has_explicit_length);
     options.SetNeedsZeroTermination(!has_explicit_length);
     options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                TypeSummaryCapping::eTypeSummaryUncapped);
     options.SetBinaryZeroIsTerminator(!has_explicit_length);
     options.SetLanguage(summary_options.GetLanguage());
     if (has_explicit_length)
       return StringPrinter::ReadStringAndDumpToStream<
           StringPrinter::StringElementType::UTF8>(options);
     else
       return StringPrinter::ReadStringAndDumpToStream<
           StringPrinter::StringElementType::ASCII>(options);
   } else {
     uint64_t location = valobj_addr + 2 * ptr_size;
     location = process_sp->ReadPointerFromMemory(location, error);
     if (error.Fail())
       return false;
     if (has_explicit_length && !has_null)
       explicit_length++; // account for the fact that there is no NULL and we
                          // need to have one added
     options.SetLocation(location);
     options.SetProcessSP(process_sp);
     options.SetStream(&stream);
     options.SetSourceSize(explicit_length);
+    options.SetHasSourceSize(has_explicit_length);
     options.SetIgnoreMaxLength(summary_options.GetCapping() ==
                                TypeSummaryCapping::eTypeSummaryUncapped);
     options.SetLanguage(summary_options.GetLanguage());
     return StringPrinter::ReadStringAndDumpToStream<
         StringPrinter::StringElementType::ASCII>(options);
   }
 }