GP-6363 - Gnu Demangler - Updated the legacy GnuDemangler v2.24 to

handle qualifiers being used along with the 'F' character.

GPL/DemanglerGnu/src/demangler_gnu_v2_24/README.txt

@@ -37,6 +37,13 @@ method from cxxfilt.c and placed it, along with supporting methods, into cplus-d
 allows us to perform a simple build of the stand alone demangler, with less source files 
 required.
 
+Update January 2026
+
+Fixed a bug seen in older mangled symbols that use an 'F' character for functions.  We added a 
+function to handle this case,  isQualifiersAndFunc().  This function called from inside the 
+demangle_signature() function.
+
+
 cp-demangle.c *
 
 This file contains a small, two-line change to send a newline character ('\n') along with 

GPL/DemanglerGnu/src/demangler_gnu_v2_24/c/cplus-dem.c

@@ -819,6 +819,33 @@ cplus_demangle_name_to_style (const char *name)
   return unknown_demangling;
 }
 
+
+/* Scans to see if mangled is a set of optional qualifiers and a function. */
+static int /* bool */
+isQualifiersAndFunc(const char *mangled)
+{
+
+	int i = 0;
+	while (1)
+	{
+
+		switch (mangled[i++])
+		{
+		case 'C':
+		case 'V':
+		case 'u':
+			/*qualifier*/
+			break;
+		case 'F':
+			/* function */
+			return 1;
+		default:
+			/* anything else is not a qualifier or function */
+			return 0;
+		}
+	}
+}
+
 /* char *cplus_demangle (const char *mangled, int options)
 
    If MANGLED is a mangled function name produced by GNU C++, then
@@ -1485,8 +1512,10 @@ demangle_signature (struct work_stuff *work,
 	    {
               /* EDG and others will have the "F", so we let the loop cycle
                  if we are looking at one. */
-              if (**mangled != 'F')
+              // if (**mangled != 'F')
+              if (!isQualifiersAndFunc(*mangled)) {
                  expect_func = 1;
+              }
 	    }
 	  oldmangled = NULL;
 	  break;

Ghidra/Features/GnuDemangler/src/test/java/ghidra/app/util/demangler/GnuDemanglerParserTest.java

@@ -181,6 +181,23 @@ public class GnuDemanglerParserTest extends AbstractGenericTest {
 		assertEquals("float", parameters.get(3).getType().getSignature());
 	}
 
+	@Test
+	public void testLegacy_DemangledFunctionCharacter() throws Exception {
+
+		// This is only supported in the older v24 demangler.  The 'F' character was not being 
+		// correctly demangled.  The native demangler was updated to fix this.
+		String mangled = "foo__03FooCFUcT1";
+		process = GnuDemanglerNativeProcess
+				.getDemanglerNativeProcess(GnuDemanglerOptions.GNU_DEMANGLER_V2_24);
+		String demangled = process.demangle(mangled);
+		assertEquals("Foo::foo(unsigned char, unsigned char) const", demangled);
+
+		DemangledObject object = parser.parse(mangled, demangled);
+		assertType(object, DemangledFunction.class);
+		assertName(object, "foo", "Foo");
+		assertEquals("undefined Foo::foo(unsigned char,unsigned char)", object.getSignature());
+	}
+
 	@Test
 	public void testTemplates_TemplatedType() throws Exception {
 		String mangled =