diff --git a/lld/MachO/Writer.cpp b/lld/MachO/Writer.cpp
--- a/lld/MachO/Writer.cpp
+++ b/lld/MachO/Writer.cpp
@@ -134,7 +134,11 @@
     c->nsects = seg->numNonHiddenSections();
 
     for (OutputSection *osec : seg->getSections()) {
-      c->filesize += osec->getFileSize();
+      if (!isZeroFill(osec->flags)) {
+        assert(osec->fileOff >= seg->fileOff);
+        c->filesize = std::max(
+            c->filesize, osec->fileOff + osec->getFileSize() - seg->fileOff);
+      }
 
       if (osec->isHidden())
         continue;
@@ -454,6 +458,8 @@
   seg->fileOff = fileOff;
 
   for (auto *osec : seg->getSections()) {
+    if (!osec->isNeeded())
+      continue;
     addr = alignTo(addr, osec->align);
     fileOff = alignTo(fileOff, osec->align);
     osec->addr = addr;
diff --git a/lld/test/MachO/section-headers.s b/lld/test/MachO/section-headers.s
--- a/lld/test/MachO/section-headers.s
+++ b/lld/test/MachO/section-headers.s
@@ -1,7 +1,7 @@
 # REQUIRES: x86
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %s -o %t.o
 # RUN: lld -flavor darwinnew -o %t %t.o
-# RUN: llvm-readobj --section-headers %t | FileCheck %s
+# RUN: llvm-readobj --section-headers --macho-segment %t | FileCheck %s
 
 # CHECK:      Name: __text
 # CHECK-NEXT: Segment: __TEXT
@@ -25,11 +25,21 @@
 
 # CHECK:      Name: maxlen_16ch_name
 # CHECK-NEXT: Segment: __TEXT
-# CHECK-NOT:  }
-# CHECK:      Alignment: 3
+# CHECK-NEXT: Address:
+# CHECK-NEXT: Size: [[#%x, LAST_SEC_SIZE:]]
+# CHECK-NEXT: Offset: [[#%u, LAST_SEC_OFF:]]
+# CHECK-NEXT: Alignment: 3
 # CHECK-NOT:  }
 # CHECK:      Type: Regular (0x0)
 
+# CHECK-LABEL: Segment {
+# CHECK:       Name: __TEXT
+# CHECK-NEXT:  Size:
+# CHECK-NEXT:  vmaddr:
+# CHECK-NEXT:  vmsize:
+# CHECK-NEXT:  fileoff: 0
+# CHECK-NEXT:  filesize: [[#%u, LAST_SEC_SIZE + LAST_SEC_OFF]]
+
 .text
 .align 1
 .global _main
diff --git a/lld/test/MachO/segments.s b/lld/test/MachO/segments.s
--- a/lld/test/MachO/segments.s
+++ b/lld/test/MachO/segments.s
@@ -1,49 +1,58 @@
-# REQUIRES: x86
+# REQUIRES: x86, shell
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %s -o %t.o
 # RUN: lld -flavor darwinnew -o %t %t.o
-# RUN: llvm-readobj --macho-segment %t | FileCheck %s
+# RUN: (llvm-readobj --macho-segment %t; echo "Total file size"; wc -c %t) | FileCheck %s
 
 ## These two segments must always be present at the start of an executable.
 # CHECK-NOT:  Segment {
 # CHECK:      Segment {
-# CHECK:        Cmd: LC_SEGMENT_64
-# CHECK:        Name: __PAGEZERO
-# CHECK:        Size: 72
-# CHECK:        vmaddr: 0x0
-# CHECK:        vmsize: 0x100000000
-# CHECK:        fileoff: 0
-# CHECK:        filesize: 0
+# CHECK-NEXT:   Cmd: LC_SEGMENT_64
+# CHECK-NEXT:   Name: __PAGEZERO
+# CHECK-NEXT:   Size: 72
+# CHECK-NEXT:   vmaddr: 0x0
+# CHECK-NEXT:   vmsize: 0x100000000
+# CHECK-NEXT:   fileoff: 0
+# CHECK-NEXT:   filesize: 0
 ## The kernel won't execute a binary with the wrong protections for __PAGEZERO.
-# CHECK:        maxprot: ---
-# CHECK:        initprot: ---
-# CHECK:        nsects: 0
-# CHECK:        flags: 0x0
-# CHECK:      }
-# CHECK:      Segment {
-# CHECK:        Cmd: LC_SEGMENT_64
-# CHECK:        Name: __TEXT
-# CHECK:        Size: 152
-# CHECK:        vmaddr: 0x100000000
-# CHECK:        vmsize:
+# CHECK-NEXT:   maxprot: ---
+# CHECK-NEXT:   initprot: ---
+# CHECK-NEXT:   nsects: 0
+# CHECK-NEXT:   flags: 0x0
+# CHECK-NEXT: }
+# CHECK-NEXT: Segment {
+# CHECK-NEXT:   Cmd: LC_SEGMENT_64
+# CHECK-NEXT:   Name: __TEXT
+# CHECK-NEXT:   Size: 152
+# CHECK-NEXT:   vmaddr: 0x100000000
+# CHECK-NEXT:   vmsize:
 ## dyld3 assumes that the __TEXT segment starts from the file header
-# CHECK:        fileoff: 0
-# CHECK:        filesize:
-# CHECK:        maxprot: rwx
-# CHECK:        initprot: r-x
-# CHECK:        nsects: 1
-# CHECK:        flags: 0x0
-# CHECK:      }
+# CHECK-NEXT:   fileoff: 0
+# CHECK-NEXT:   filesize:
+# CHECK-NEXT:   maxprot: rwx
+# CHECK-NEXT:   initprot: r-x
+# CHECK-NEXT:   nsects: 1
+# CHECK-NEXT:   flags: 0x0
+# CHECK-NEXT: }
 
 ## Check that we handle max-length names correctly.
 # CHECK:      Cmd: LC_SEGMENT_64
 # CHECK-NEXT: Name: maxlen_16ch_name
 
-## This segment must always be present at the end of an executable.
+## This segment must always be present at the end of an executable, and cover
+## its last byte.
 # CHECK:      Name: __LINKEDIT
-# CHECK:      maxprot: rwx
-# CHECK:      initprot: r--
+# CHECK-NEXT: Size:
+# CHECK-NEXT: vmaddr:
+# CHECK-NEXT: vmsize:
+# CHECK-NEXT: fileoff: [[#%u, LINKEDIT_OFF:]]
+# CHECK-NEXT: filesize: [[#%u, LINKEDIT_SIZE:]]
+# CHECK-NEXT: maxprot: rwx
+# CHECK-NEXT: initprot: r--
 # CHECK-NOT:  Cmd: LC_SEGMENT_64
 
+# CHECK-LABEL: Total file size
+# CHECK-NEXT:  [[#%u, LINKEDIT_OFF + LINKEDIT_SIZE]]
+
 .text
 .global _main
 _main: