Index: ELF/LinkerScript.cpp
===================================================================
--- ELF/LinkerScript.cpp
+++ ELF/LinkerScript.cpp
@@ -642,6 +642,11 @@
     Dot = CurMemRegion->Offset;
   switchTo(Sec);
 
+  // We do not support custom layout for compressed debug sectons.
+  // At this point we already know their size and have compressed content.
+  if (CurOutSec->Flags & SHF_COMPRESSED)
+    return;
+
   for (BaseCommand *C : Cmd->Commands)
     process(*C);
 }
Index: ELF/OutputSections.cpp
===================================================================
--- ELF/OutputSections.cpp
+++ ELF/OutputSections.cpp
@@ -93,6 +93,11 @@
       !Name.startswith(".debug_"))
     return;
 
+  // We call maybeCompress() early and for linkerscript case need to assign offsets,
+  // because that was not done yet. That finalizes mergeable synthetic sections and
+  // also finds output section total size for use in compressing code below.
+  assignOffsets();
+
   // Create a section header.
   ZDebugHeader.resize(sizeof(Elf_Chdr));
   auto *Hdr = reinterpret_cast<Elf_Chdr *>(ZDebugHeader.data());
Index: test/ELF/linkerscript/Inputs/compress-debug-sections.s
===================================================================
--- test/ELF/linkerscript/Inputs/compress-debug-sections.s
+++ test/ELF/linkerscript/Inputs/compress-debug-sections.s
@@ -0,0 +1,20 @@
+.section .debug_str,"MS",@progbits,1
+.Linfo_string0:
+  .asciz "CCC"
+.Linfo_string1:
+  .asciz "DDD"
+
+.section .debug_gnu_pubtypes,"",@progbits
+.long .LpubTypes_end0-.LpubTypes_begin0 # Length of Public Types Info
+.LpubTypes_begin0:
+ .short 2                      # DWARF Version
+ .long 0                       # Offset of Compilation Unit Info
+ .long 36                      # Compilation Unit Length
+ .long 36                      # DIE offset
+ .byte 144                     # Kind: TYPE, STATIC
+ .asciz "ccc"                  # External Name
+ .long 36                      # DIE offset
+ .byte 144                     # Kind: TYPE, STATIC
+ .asciz "ddd"                  # External Name
+ .long 0                       # End Mark
+.LpubTypes_end0:
Index: test/ELF/linkerscript/compress-debug-sections.s
===================================================================
--- test/ELF/linkerscript/compress-debug-sections.s
+++ test/ELF/linkerscript/compress-debug-sections.s
@@ -0,0 +1,44 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux \
+# RUN:   %S/Inputs/compress-debug-sections.s -o %t1.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t2.o
+# RUN: echo "SECTIONS { }" > %t.script
+# RUN: ld.lld %t1.o %t2.o %t.script -o %t --compress-debug-sections=zlib
+# RUN: llvm-dwarfdump %t | FileCheck %s
+
+# CHECK:       .debug_str contents:
+# CHECK-NEXT:    CCC
+# CHECK-NEXT:    DDD
+# CHECK-NEXT:    AAA
+# CHECK-NEXT:    BBB
+# CHECK:      .debug_gnu_pubtypes contents:
+# CHECK-NEXT:   length = 0x00000020 version = 0x0002 unit_offset = 0x00000000 unit_size = 0x00000024
+# CHECK-NEXT:   Offset     Linkage  Kind     Name
+# CHECK-NEXT:   0x00000024 STATIC   TYPE     "ccc"
+# CHECK-NEXT:   0x00000024 STATIC   TYPE     "ddd"
+# CHECK-NEXT:   length = 0x00000020 version = 0x0002 unit_offset = 0x00000000 unit_size = 0x00000024
+# CHECK-NEXT:   Offset     Linkage  Kind     Name
+# CHECK-NEXT:   0x00000024 STATIC   TYPE     "aaa"
+# CHECK-NEXT:   0x00000024 STATIC   TYPE     "bbb"
+
+.section .debug_str,"MS",@progbits,1
+.Linfo_string0:
+  .asciz "AAA"
+.Linfo_string1:
+  .asciz "BBB"
+   
+.section .debug_gnu_pubtypes,"",@progbits
+.long .LpubTypes_end0-.LpubTypes_begin0 # Length of Public Types Info
+.LpubTypes_begin0:
+ .short 2                      # DWARF Version
+ .long 0                       # Offset of Compilation Unit Info
+ .long 36                      # Compilation Unit Length
+ .long 36                      # DIE offset
+ .byte 144                     # Kind: TYPE, STATIC
+ .asciz "aaa"                  # External Name
+ .long 36                      # DIE offset
+ .byte 144                     # Kind: TYPE, STATIC
+ .asciz "bbb"                  # External Name
+ .long 0                       # End Mark
+.LpubTypes_end0: