Account for new header layout in DWARF v5

Fixes #198

core/org.eclipse.cdt.core.tests/misc/org/eclipse/cdt/utils/elf/ElfTest.java

@@ -40,25 +40,41 @@ public class ElfTest {
 
 	private static final String SYMTAB_NAME = ".symtab";
 
-	@Parameters(name = "{0}")
-	public static Collection<Object[]> elfArchitectures() {
-		return Arrays.asList(new Object[][] {
-				{ "BE32", "ppc", "resources/elf/unit_test/simple-be32.elf", 35, "0x00000000", "0x100001a8", 75,
-						"0x10000518" },
-				{ "BE64", "ppc64", "resources/elf/unit_test/simple-be64.elf", 34, "0x0000000000000000",
-						"0x0000000010000240", 69, "0x000000001001fea0" },
-				{ "LE32", "x86", "resources/elf/unit_test/simple-le32.elf", 36, "0x00000000", "0x080481cc", 70,
-						"0x080483e5" },
-				{ "LE64", "x86_64", "resources/elf/unit_test/simple-le64.elf", 36, "0x0000000000000000",
-						"0x00000000004002b8", 68, "0x00000000004004e4" }, });
-	}
-
-	private static final Collection<String> functions = Arrays.asList("", "crtstuff.c", "simple.c", "crtstuff.c",
+	/**
+	 * Different elfs, being built on different architectures, etc may have different
+	 * contents in their symbol tables.
+	 *
+	 * See {@link #elfArchitectures()} for the mapping of which elf files contain which
+	 * sets of functions
+	 */
+	private static final Collection<String> functions1 = Arrays.asList("", "crtstuff.c", "simple.c", "crtstuff.c",
 			"_ITM_deregisterTMCloneTable", "__gmon_start__", "_Jv_RegisterClasses", "_ITM_registerTMCloneTable",
 			"_init", "_start", "deregister_tm_clones", "register_tm_clones", "__do_global_dtors_aux", "frame_dummy",
 			"function", "main", "__libc_csu_init", "__libc_csu_fini", "_fini", "_IO_stdin_used", "__FRAME_END__",
 			"__JCR_LIST__", "__JCR_END__", "_DYNAMIC", "data_start", "__data_start", "__dso_handle", "_edata",
 			"__bss_start", "__TMC_END__", "_end");
+	private static final Collection<String> functions2 = Arrays.asList("", "crtstuff.c", "simple.c", "crtstuff.c",
+			"_ITM_deregisterTMCloneTable", "__gmon_start__", "_ITM_registerTMCloneTable", "_init", "_start",
+			"deregister_tm_clones", "register_tm_clones", "__do_global_dtors_aux", "frame_dummy", "function", "main",
+			"_fini", "_IO_stdin_used", "__FRAME_END__", "_DYNAMIC", "data_start", "__data_start", "__dso_handle",
+			"_edata", "__bss_start", "__TMC_END__", "_end");
+
+	@Parameters(name = "{0}")
+	public static Collection<Object[]> elfArchitectures() {
+		return Arrays.asList(new Object[][] {
+				{ "BE32", "BE32", "ppc", "resources/elf/unit_test/simple-be32.elf", 35, "0x00000000", "0x100001a8", 75,
+						"0x10000518", Attribute.ELF_TYPE_EXE, functions1 },
+				{ "BE64", "BE64", "ppc64", "resources/elf/unit_test/simple-be64.elf", 34, "0x0000000000000000",
+						"0x0000000010000240", 69, "0x000000001001fea0", Attribute.ELF_TYPE_EXE, functions1 },
+				{ "LE32", "LE32", "x86", "resources/elf/unit_test/simple-le32.elf", 36, "0x00000000", "0x080481cc", 70,
+						"0x080483e5", Attribute.ELF_TYPE_EXE, functions1 },
+				{ "LE64", "LE64", "x86_64", "resources/elf/unit_test/simple-le64.elf", 36, "0x0000000000000000",
+						"0x00000000004002b8", 68, "0x00000000004004e4", Attribute.ELF_TYPE_EXE, functions1 },
+				{ "DWARF4", "LE64", "x86_64", "resources/elf/unit_test/simple-dwarf4.elf", 34, "0x0000000000000000",
+						"0x00000000000003d8", 34, "0x000000000000113b", Attribute.ELF_TYPE_SHLIB, functions2 },
+				{ "DWARF5", "LE64", "x86_64", "resources/elf/unit_test/simple-dwarf5.elf", 35, "0x0000000000000000",
+						"0x00000000000003d8", 34, "0x000000000000113b", Attribute.ELF_TYPE_SHLIB, functions2 }, });
+	}
 
 	private final String memoryArchitecture;
 	private final String arch;
@@ -68,9 +84,12 @@ public static Collection<Object[]> elfArchitectures() {
 	private final String dynsymBaseAddress;
 	private final int nbSymbols;
 	private final String mainAddress;
+	private final int elfType;
+	private final Collection<String> functions;
 
-	public ElfTest(String mArch, String architecture, String path, int sections, String symBaseAddress,
-			String dynBaseAddress, int symbolCount, String mainAddr) throws IOException {
+	public ElfTest(String testName, String mArch, String architecture, String path, int sections, String symBaseAddress,
+			String dynBaseAddress, int symbolCount, String mainAddr, int elfType, Collection<String> functions)
+			throws IOException {
 		memoryArchitecture = mArch;
 		nbSections = sections;
 		elf = new Elf(path);
@@ -79,6 +98,8 @@ public ElfTest(String mArch, String architecture, String path, int sections, Str
 		dynsymBaseAddress = dynBaseAddress;
 		nbSymbols = symbolCount;
 		mainAddress = mainAddr;
+		this.elfType = elfType;
+		this.functions = functions;
 	}
 
 	/**
@@ -92,12 +113,10 @@ public void testGetSections() throws IOException {
 		assertNotNull(sectionByName);
 		assertEquals(arch + ": " + "symbol table", SYMTAB_NAME, sectionByName.toString());
 		assertEquals(arch + ": " + "binary address", symtabBaseAddress, sectionByName.sh_addr.toHexAddressString());
-		assertEquals(arch + ": " + "sh_name", 1, sectionByName.sh_name);
 		sectionByName = elf.getSectionByName(".dynsym");
 		assertNotNull(sectionByName);
 		assertEquals(arch + ": " + "dynamic symbols", ".dynsym", sectionByName.toString());
 		assertEquals(arch + ": " + "binary address", dynsymBaseAddress, sectionByName.sh_addr.toHexAddressString());
-		assertEquals(arch + ": " + "sh_name", 78L, sectionByName.sh_name);
 	}
 
 	/**
@@ -150,7 +169,7 @@ public void testGetAttributes() throws IOException {
 				memoryArchitecture.endsWith("32") ? unsigned32BitAddress : unsigned64BitAddress,
 				attributes.getAddressFactory().getMax().getValue());
 		assertEquals(arch + ": " + "debug type", Attribute.DEBUG_TYPE_DWARF, attributes.getDebugType());
-		assertEquals(arch + ": " + "elf type", Attribute.ELF_TYPE_EXE, attributes.getType());
+		assertEquals(arch + ": " + "elf type", elfType, attributes.getType());
 	}
 
 	@Test

core/org.eclipse.cdt.core.tests/resources/elf/unit_test/Makefile

@@ -1,2 +1,11 @@
 #just an example
-gcc simple.c -g -o simple.elf
+# gcc simple.c -g -o simple.elf
+
+simple-dwarf4.elf:
+	gcc simple.c -g -gdwarf-4 -o simple-dwarf4.elf
+
+# This needs to run on a GCC that fully supports DWARF v5, e.g. Ubuntu 22.04
+# e.g. docker run --rm -it -v $PWD:/work -w /work ubuntu:22.04 /bin/bash
+# apt-get update && apt-get install -y --no-install-recommends build-essential
+simple-dwarf5.elf:
+	gcc simple.c -g -gdwarf-5 -o simple-dwarf5.elf

core/org.eclipse.cdt.core/utils/org/eclipse/cdt/utils/debug/dwarf/Dwarf.java

@@ -460,11 +460,22 @@ void parseDebugInfo(IDebugEntryRequestor requestor) {
 					header.offsetSize = sectionLength.offsetSize;
 
 					header.version = read_2_bytes(data);
-					if (header.offsetSize == 8)
-						header.abbreviationOffset = (int) read_8_bytes(data);
-					else
-						header.abbreviationOffset = read_4_bytes(data);
-					header.addressSize = data.get();
+					if (header.version >= 5) {
+						// XXX: We don't use this new field in DWARF v5 yet
+						var unit_type = data.get();
+						header.addressSize = data.get();
+
+						if (header.offsetSize == 8)
+							header.abbreviationOffset = (int) read_8_bytes(data);
+						else
+							header.abbreviationOffset = read_4_bytes(data);
+					} else {
+						if (header.offsetSize == 8)
+							header.abbreviationOffset = (int) read_8_bytes(data);
+						else
+							header.abbreviationOffset = read_4_bytes(data);
+						header.addressSize = data.get();
+					}
 
 					if (printEnabled) {
 						System.out.println("Compilation Unit @ " + Long.toHexString(data.position())); //$NON-NLS-1$
@@ -476,10 +487,20 @@ void parseDebugInfo(IDebugEntryRequestor requestor) {
 					// A 4-byte or 12-byte unsigned integer representing the length of the .debug_info
 					// contribution for that compilation unit, not including the length field itself.
 					ByteBuffer entryBuffer = data.slice();
-					entryBuffer.limit(((int) header.length) - (header.offsetSize == 8 ? 11 : 7));
+					int newLimit = ((int) header.length) - (header.offsetSize == 8 ? 11 : 7);
+					if (header.version >= 5) {
+						// account for new field in DWARF v5
+						newLimit -= 1;
+					}
+					entryBuffer.limit(newLimit);
 					parseDebugInfoEntry(requestor, entryBuffer, abbrevs, header);
 
-					data.position(data.position() + ((int) header.length) - (header.offsetSize == 8 ? 11 : 7));
+					int newLimit2 = ((int) header.length) - (header.offsetSize == 8 ? 11 : 7);
+					if (header.version >= 5) {
+						// account for new field in DWARF v5
+						newLimit2 -= 1;
+					}
+					data.position(data.position() + newLimit2);
 
 					if (printEnabled)
 						System.out.println();