Index: llvm/test/Object/invalid.test
===================================================================
--- llvm/test/Object/invalid.test
+++ llvm/test/Object/invalid.test
@@ -489,7 +489,7 @@
 # RUN: yaml2obj %s --docnum=22 -o %t22
 # RUN: llvm-readobj --dyn-relocations %t22 2>&1 | FileCheck -DFILE=%t22 --check-prefix=DYN-TABLE-PHDR %s
 
-# DYN-TABLE-PHDR: warning: '[[FILE]]': PT_DYNAMIC segment offset + size exceeds the size of the file
+# DYN-TABLE-PHDR: warning: '[[FILE]]': PT_DYNAMIC segment offset (0xffff0000) + file size (0x0) exceeds the size of the file (0x150)
 
 --- !ELF
 FileHeader:
@@ -506,7 +506,9 @@
 
 # RUN: yaml2obj %s --docnum=23 -o %t23
 # RUN: llvm-readobj --dyn-relocations %t23 2>&1 \
-# RUN:  | FileCheck -DFILE=%t23 --check-prefix=DYN-TABLE-PHDR %s
+# RUN:  | FileCheck -DFILE=%t23 --check-prefix=DYN-TABLE-PHDR2 %s
+
+# DYN-TABLE-PHDR2: warning: '[[FILE]]': PT_DYNAMIC segment offset (0x78) + file size (0xffff0000) exceeds the size of the file (0x1a8)
 
 --- !ELF
 FileHeader:
Index: llvm/test/tools/llvm-readobj/ELF/malformed-pt-dynamic.test
===================================================================
--- llvm/test/tools/llvm-readobj/ELF/malformed-pt-dynamic.test
+++ llvm/test/tools/llvm-readobj/ELF/malformed-pt-dynamic.test
@@ -1,47 +1,69 @@
-# If the offset and/or size fields of the PT_DYNAMIC field become corrupted,
-# we should report a sensible message.
+## If the offset and/or size fields of the PT_DYNAMIC field become corrupted,
+## we should report a sensible message.
 
-# Creating such a malformed file is hard. The easiest way to simulate it is to
-# truncate the file. Note that the section headers must first be stripped or
-# llvm-readobj will fail to parse the file due to the section header table
-# offset pointing outside the file.
+## Case A: Test case where the size is too large to fit in the file, but the start is
+##         within the file.
+# RUN: yaml2obj %s -DFILESIZE=0x119 -o %t1
+# RUN: llvm-readobj %t1 --dynamic-table 2>&1 | FileCheck -DFILE=%t1 %s --check-prefix=WARN1
+# RUN: llvm-readelf %t1 --dynamic-table 2>&1 | FileCheck -DFILE=%t1 %s --check-prefix=WARN1
 
-# RUN: yaml2obj %s -o %t.base
-# RUN: llvm-objcopy --strip-sections %t.base %t.stripped
+# WARN1: warning: '[[FILE]]': PT_DYNAMIC segment offset (0x1000) + file size (0x119) exceeds the size of the file (0x1118)
 
-# Test case where the size is too large to fit in the file, but the start is
-# within the file.
-# RUN: cp %t.stripped %t.truncated1
-# RUN: %python -c "with open(r'%t.truncated1', 'r+') as f: f.truncate(0x1001)"
-# RUN: llvm-readobj %t.truncated1 --dynamic-table 2>&1 | FileCheck -DFILE=%t.truncated1 %s
+## Case B: Test case where the offset is too large to be in the file.
+# RUN: yaml2obj %s -DOFFSET=0x1119 -o %t2
+# RUN: llvm-readobj %t2 --dynamic-table 2>&1 | FileCheck -DFILE=%t2 %s --check-prefix=WARN2
+# RUN: llvm-readelf %t2 --dynamic-table 2>&1 | FileCheck -DFILE=%t2 %s --check-prefix=WARN2
 
-# Test case where the offset is too large to be in the file.
-# RUN: cp %t.stripped %t.truncated2
-# RUN: %python -c "with open(r'%t.truncated2', 'r+') as f: f.truncate(0xFFF)"
-# RUN: llvm-readobj %t.truncated2 --dynamic-table 2>&1 | FileCheck -DFILE=%t.truncated2 %s
+# WARN2: warning: '[[FILE]]': PT_DYNAMIC segment offset (0x1119) + file size (0x10) exceeds the size of the file (0x1118)
 
-# CHECK: warning: '[[FILE]]': PT_DYNAMIC segment offset + size exceeds the size of the file
+## Case C: test we report a warning when the offset + the file size of the PT_DYNAMIC is so large a
+##         value that it overflows the platform address size type.
+
+# RUN: yaml2obj %s -DOFFSET=0xffffffffffffffff -o %t3
+# RUN: llvm-readobj %t3 --dynamic-table 2>&1 | FileCheck -DFILE=%t3 %s --check-prefix=WARN3
+# RUN: llvm-readelf %t3 --dynamic-table 2>&1 | FileCheck -DFILE=%t3 %s --check-prefix=WARN3
+
+# WARN3: warning: '[[FILE]]': PT_DYNAMIC segment offset (0xffffffffffffffff) + file size (0x10) exceeds the size of the file (0x1118)
+
+# RUN: yaml2obj %s -DFILESIZE=0xffffffffffffffff -o %t4
+# RUN: llvm-readobj %t4 --dynamic-table 2>&1 | FileCheck -DFILE=%t4 %s --check-prefix=WARN4
+# RUN: llvm-readelf %t4 --dynamic-table 2>&1 | FileCheck -DFILE=%t4 %s --check-prefix=WARN4
+
+# WARN4: warning: '[[FILE]]': PT_DYNAMIC segment offset (0x1000) + file size (0xffffffffffffffff) exceeds the size of the file (0x1118)
+
+## Case D: the same as "Case C", but for a 32-bit object.
+
+# RUN: yaml2obj %s -DBITS=32 -DOFFSET=0xffffffff -o %t5
+# RUN: llvm-readobj %t5 --dynamic-table 2>&1 | FileCheck -DFILE=%t5 %s --check-prefix=WARN5
+# RUN: llvm-readelf %t5 --dynamic-table 2>&1 | FileCheck -DFILE=%t5 %s --check-prefix=WARN5
+
+# WARN5: warning: '[[FILE]]': PT_DYNAMIC segment offset (0xffffffff) + file size (0x8) exceeds the size of the file (0x10ac)
+
+# RUN: yaml2obj %s -DBITS=32 -DFILESIZE=0xffffffff -o %t6
+# RUN: llvm-readobj %t6 --dynamic-table 2>&1 | FileCheck -DFILE=%t6 %s --check-prefix=WARN6
+# RUN: llvm-readelf %t6 --dynamic-table 2>&1 | FileCheck -DFILE=%t6 %s --check-prefix=WARN6
+
+# WARN6: warning: '[[FILE]]': PT_DYNAMIC segment offset (0x1000) + file size (0xffffffff) exceeds the size of the file (0x10ac)
 
 --- !ELF
 FileHeader:
-  Class:   ELFCLASS64
+  Class:   ELFCLASS[[BITS=64]]
   Data:    ELFDATA2LSB
   Type:    ET_EXEC
-  Machine: EM_X86_64
+  Machine: EM_NONE
 Sections:
-  - Name:         .dynamic
-    Type:         SHT_DYNAMIC
-    Address:      0x1000
-    AddressAlign: 0x1000
+  - Name:     .dynamic
+    Type:     SHT_DYNAMIC
+    Address:  0x1000
+    Offset:   0x1000
+    ShOffset: [[OFFSET=<none>]]
     Entries:
       - Tag:   DT_NULL
         Value: 0
 ProgramHeaders:
-  - Type: PT_LOAD
-    VAddr: 0x1000
-    Sections:
-      - Section: .dynamic
-  - Type: PT_DYNAMIC
-    VAddr: 0x1000
+  - Type:     PT_DYNAMIC
+    FileSize: [[FILESIZE=<none>]]
     Sections:
       - Section: .dynamic
+SectionHeaderTable:
+  NoHeaders: true
Index: llvm/tools/llvm-readobj/ELFDumper.cpp
===================================================================
--- llvm/tools/llvm-readobj/ELFDumper.cpp
+++ llvm/tools/llvm-readobj/ELFDumper.cpp
@@ -1919,12 +1919,16 @@
     break;
   }
 
-  if (DynamicPhdr && DynamicPhdr->p_offset + DynamicPhdr->p_filesz >
-                         ObjF->getMemoryBufferRef().getBufferSize()) {
-    reportWarning(
-        createError(
-            "PT_DYNAMIC segment offset + size exceeds the size of the file"),
-        ObjF->getFileName());
+  if (DynamicPhdr && ((DynamicPhdr->p_offset + DynamicPhdr->p_filesz >
+                       ObjF->getMemoryBufferRef().getBufferSize()) ||
+                      (DynamicPhdr->p_offset + DynamicPhdr->p_filesz <
+                       DynamicPhdr->p_offset))) {
+    reportUniqueWarning(createError(
+        "PT_DYNAMIC segment offset (0x" +
+        Twine::utohexstr(DynamicPhdr->p_offset) + ") + file size (0x" +
+        Twine::utohexstr(DynamicPhdr->p_filesz) +
+        ") exceeds the size of the file (0x" +
+        Twine::utohexstr(ObjF->getMemoryBufferRef().getBufferSize()) + ")"));
     // Don't use the broken dynamic header.
     DynamicPhdr = nullptr;
   }