diff --git a/llvm/lib/Transforms/Utils/InlineFunction.cpp b/llvm/lib/Transforms/Utils/InlineFunction.cpp
--- a/llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ b/llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -1537,7 +1537,8 @@
 
 static void HandleByValArgumentInit(Type *ByValType, Value *Dst, Value *Src,
                                     Module *M, BasicBlock *InsertBlock,
-                                    InlineFunctionInfo &IFI) {
+                                    InlineFunctionInfo &IFI,
+                                    Function *CalledFunc) {
   IRBuilder<> Builder(InsertBlock, InsertBlock->begin());
 
   Value *Size =
@@ -1546,8 +1547,15 @@
   // Always generate a memcpy of alignment 1 here because we don't know
   // the alignment of the src pointer.  Other optimizations can infer
   // better alignment.
-  Builder.CreateMemCpy(Dst, /*DstAlign*/ Align(1), Src,
-                       /*SrcAlign*/ Align(1), Size);
+  CallInst *CI = Builder.CreateMemCpy(Dst, /*DstAlign*/ Align(1), Src,
+                                      /*SrcAlign*/ Align(1), Size);
+
+  // The verifier requires that all calls of debug-info-bearing functions
+  // from debug-info-bearing functions have a debug location (for inlining
+  // purposes). Assign a dummy location to satisfy the constraint.
+  if (!CI->getDebugLoc() && InsertBlock->getParent()->getSubprogram())
+    if (DISubprogram *SP = CalledFunc->getSubprogram())
+      CI->setDebugLoc(DILocation::get(SP->getContext(), 0, 0, SP));
 }
 
 /// When inlining a call site that has a byval argument,
@@ -2242,7 +2250,7 @@
     // Inject byval arguments initialization.
     for (ByValInit &Init : ByValInits)
       HandleByValArgumentInit(Init.Ty, Init.Dst, Init.Src, Caller->getParent(),
-                              &*FirstNewBlock, IFI);
+                              &*FirstNewBlock, IFI, CalledFunc);
 
     std::optional<OperandBundleUse> ParentDeopt =
         CB.getOperandBundle(LLVMContext::OB_deopt);
diff --git a/llvm/test/Transforms/Inline/byval-dbg.ll b/llvm/test/Transforms/Inline/byval-dbg.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/Inline/byval-dbg.ll
@@ -0,0 +1,49 @@
+; RUN: opt < %s -passes=inline -S | FileCheck %s
+
+; Check that the memcpy generated by byval lowering is decorated by debuginfo.
+
+target datalayout = "p:32:32-p1:64:64-p2:16:16-n16:32:64"
+
+%struct.ss = type { i32, i64 }
+
+define internal void @f(ptr byval(%struct.ss)  %b) nounwind !dbg !4 {
+entry:
+	%tmp = getelementptr %struct.ss, ptr %b, i32 0, i32 0		; <ptr> [#uses=2]
+	%tmp1 = load i32, ptr %tmp, align 4		; <i32> [#uses=1]
+	%tmp2 = add i32 %tmp1, 1		; <i32> [#uses=1]
+	store i32 %tmp2, ptr %tmp, align 4
+	ret void
+}
+
+define i32 @test1() nounwind !dbg !10 {
+entry:
+	%S = alloca %struct.ss		; <ptr> [#uses=4]
+	%tmp1 = getelementptr %struct.ss, ptr %S, i32 0, i32 0		; <ptr> [#uses=1]
+	store i32 1, ptr %tmp1, align 8
+	%tmp4 = getelementptr %struct.ss, ptr %S, i32 0, i32 1		; <ptr> [#uses=1]
+	store i64 2, ptr %tmp4, align 4
+	call void @f(ptr byval(%struct.ss) %S) nounwind, !dbg !14
+	ret i32 0
+; CHECK: @test1()
+; CHECK: call void @llvm.memcpy{{.*}} !dbg
+; CHECK: ret i32 0
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!2, !3}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "/app/example.c", directory: "/app")
+!2 = !{i32 7, !"Dwarf Version", i32 4}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = distinct !DISubprogram(name: "f", scope: !5, file: !5, line: 1, type: !6, scopeLine: 1, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !9)
+!5 = !DIFile(filename: "example.c", directory: "/app")
+!6 = !DISubroutineType(types: !7)
+!7 = !{null, !8}
+!8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
+!9 = !{}
+!10 = distinct !DISubprogram(name: "test1", scope: !5, file: !5, line: 4, type: !11, scopeLine: 4, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !9)
+!11 = !DISubroutineType(types: !12)
+!12 = !{!13}
+!13 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!14 = !DILocation(line: 6, column: 1, scope: !10)