diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
--- a/llvm/lib/MC/MCAssembler.cpp
+++ b/llvm/lib/MC/MCAssembler.cpp
@@ -785,9 +785,15 @@
   }
 
   // Layout until everything fits.
-  while (layoutOnce(Layout))
+  while (layoutOnce(Layout)) {
     if (getContext().hadError())
       return;
+    // Size of fragments in one section can depend on the size of fragments in
+    // another. If any fragment has changed size, we have to re-layout (and
+    // as a result possibly further relax) all.
+    for (MCSection &Sec : *this)
+      Layout.invalidateFragmentsFrom(&*Sec.begin());
+  }
 
   DEBUG_WITH_TYPE("mc-dump", {
       errs() << "assembler backend - post-relaxation\n--\n";
diff --git a/llvm/test/MC/X86/relax-offset.s b/llvm/test/MC/X86/relax-offset.s
new file mode 100644
--- /dev/null
+++ b/llvm/test/MC/X86/relax-offset.s
@@ -0,0 +1,13 @@
+# RUN: llvm-mc -filetype=obj -triple=i386 %s | llvm-objdump - --headers | FileCheck %s
+
+  # CHECK: .text1        00000005 00000000
+  # CHECK: .text2        00000005 00000000
+
+  .section .text1
+ .skip after-before,0x0
+.Lint80_keep_stack:
+
+  .section .text2
+before:
+ jmp .Lint80_keep_stack
+after: