diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
--- a/llvm/docs/ReleaseNotes.rst
+++ b/llvm/docs/ReleaseNotes.rst
@@ -188,6 +188,10 @@
 
   * ``LLVMConstFNeg``
 
+* The ``LLVMPassManagerBuilder*`` APIs have been removed as part of the
+  deprecation and removal of the legacy pass manager for the optimization
+  pipeline. ``llvm-c/Transforms/PassBuilder.h`` is the replacement.
+
 Changes to the Go bindings
 --------------------------
 
diff --git a/llvm/include/llvm-c/Transforms/PassManagerBuilder.h b/llvm/include/llvm-c/Transforms/PassManagerBuilder.h
deleted file mode 100644
--- a/llvm/include/llvm-c/Transforms/PassManagerBuilder.h
+++ /dev/null
@@ -1,81 +0,0 @@
-/*===-- llvm-c/Transform/PassManagerBuilder.h - PMB C Interface ---*- C -*-===*\
-|*                                                                            *|
-|* Part of the LLVM Project, under the Apache License v2.0 with LLVM          *|
-|* Exceptions.                                                                *|
-|* See https://llvm.org/LICENSE.txt for license information.                  *|
-|* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception                    *|
-|*                                                                            *|
-|*===----------------------------------------------------------------------===*|
-|*                                                                            *|
-|* This header declares the C interface to the PassManagerBuilder class.      *|
-|*                                                                            *|
-\*===----------------------------------------------------------------------===*/
-
-#ifndef LLVM_C_TRANSFORMS_PASSMANAGERBUILDER_H
-#define LLVM_C_TRANSFORMS_PASSMANAGERBUILDER_H
-
-#include "llvm-c/ExternC.h"
-#include "llvm-c/Types.h"
-
-typedef struct LLVMOpaquePassManagerBuilder *LLVMPassManagerBuilderRef;
-
-LLVM_C_EXTERN_C_BEGIN
-
-/**
- * @defgroup LLVMCTransformsPassManagerBuilder Pass manager builder
- * @ingroup LLVMCTransforms
- *
- * @{
- */
-
-/** See llvm::PassManagerBuilder. */
-LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate(void);
-void LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB);
-
-/** See llvm::PassManagerBuilder::OptLevel. */
-void
-LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB,
-                                  unsigned OptLevel);
-
-/** See llvm::PassManagerBuilder::SizeLevel. */
-void
-LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB,
-                                   unsigned SizeLevel);
-
-/** See llvm::PassManagerBuilder::DisableUnitAtATime. */
-void
-LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB,
-                                            LLVMBool Value);
-
-/** See llvm::PassManagerBuilder::DisableUnrollLoops. */
-void
-LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,
-                                            LLVMBool Value);
-
-/** See llvm::PassManagerBuilder::DisableSimplifyLibCalls */
-void
-LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
-                                                 LLVMBool Value);
-
-/** See llvm::PassManagerBuilder::Inliner. */
-void
-LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB,
-                                              unsigned Threshold);
-
-/** See llvm::PassManagerBuilder::populateFunctionPassManager. */
-void
-LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB,
-                                                  LLVMPassManagerRef PM);
-
-/** See llvm::PassManagerBuilder::populateModulePassManager. */
-void
-LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,
-                                                LLVMPassManagerRef PM);
-
-/**
- * @}
- */
-
-LLVM_C_EXTERN_C_END
-
-#endif
diff --git a/llvm/include/llvm/Transforms/IPO/PassManagerBuilder.h b/llvm/include/llvm/Transforms/IPO/PassManagerBuilder.h
--- a/llvm/include/llvm/Transforms/IPO/PassManagerBuilder.h
+++ b/llvm/include/llvm/Transforms/IPO/PassManagerBuilder.h
@@ -14,7 +14,6 @@
 #ifndef LLVM_TRANSFORMS_IPO_PASSMANAGERBUILDER_H
 #define LLVM_TRANSFORMS_IPO_PASSMANAGERBUILDER_H
 
-#include "llvm-c/Transforms/PassManagerBuilder.h"
 #include <functional>
 #include <string>
 #include <vector>
@@ -123,13 +122,5 @@
   void populateModulePassManager(legacy::PassManagerBase &MPM);
 };
 
-inline PassManagerBuilder *unwrap(LLVMPassManagerBuilderRef P) {
-    return reinterpret_cast<PassManagerBuilder*>(P);
-}
-
-inline LLVMPassManagerBuilderRef wrap(PassManagerBuilder *P) {
-  return reinterpret_cast<LLVMPassManagerBuilderRef>(P);
-}
-
 } // end namespace llvm
 #endif
diff --git a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
--- a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -12,7 +12,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
-#include "llvm-c/Transforms/PassManagerBuilder.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Analysis/CFLAndersAliasAnalysis.h"
@@ -461,68 +460,3 @@
   MPM.add(createAnnotationRemarksLegacyPass());
 }
 
-LLVMPassManagerBuilderRef LLVMPassManagerBuilderCreate() {
-  PassManagerBuilder *PMB = new PassManagerBuilder();
-  return wrap(PMB);
-}
-
-void LLVMPassManagerBuilderDispose(LLVMPassManagerBuilderRef PMB) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  delete Builder;
-}
-
-void
-LLVMPassManagerBuilderSetOptLevel(LLVMPassManagerBuilderRef PMB,
-                                  unsigned OptLevel) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  Builder->OptLevel = OptLevel;
-}
-
-void
-LLVMPassManagerBuilderSetSizeLevel(LLVMPassManagerBuilderRef PMB,
-                                   unsigned SizeLevel) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  Builder->SizeLevel = SizeLevel;
-}
-
-void
-LLVMPassManagerBuilderSetDisableUnitAtATime(LLVMPassManagerBuilderRef PMB,
-                                            LLVMBool Value) {
-  // NOTE: The DisableUnitAtATime switch has been removed.
-}
-
-void
-LLVMPassManagerBuilderSetDisableUnrollLoops(LLVMPassManagerBuilderRef PMB,
-                                            LLVMBool Value) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  Builder->DisableUnrollLoops = Value;
-}
-
-void
-LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
-                                                 LLVMBool Value) {
-  // NOTE: The simplify-libcalls pass has been removed.
-}
-
-void
-LLVMPassManagerBuilderUseInlinerWithThreshold(LLVMPassManagerBuilderRef PMB,
-                                              unsigned Threshold) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  Builder->Inliner = createFunctionInliningPass(Threshold);
-}
-
-void
-LLVMPassManagerBuilderPopulateFunctionPassManager(LLVMPassManagerBuilderRef PMB,
-                                                  LLVMPassManagerRef PM) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  legacy::FunctionPassManager *FPM = unwrap<legacy::FunctionPassManager>(PM);
-  Builder->populateFunctionPassManager(*FPM);
-}
-
-void
-LLVMPassManagerBuilderPopulateModulePassManager(LLVMPassManagerBuilderRef PMB,
-                                                LLVMPassManagerRef PM) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  legacy::PassManagerBase *MPM = unwrap(PM);
-  Builder->populateModulePassManager(*MPM);
-}
diff --git a/llvm/tools/llvm-c-test/include-all.c b/llvm/tools/llvm-c-test/include-all.c
--- a/llvm/tools/llvm-c-test/include-all.c
+++ b/llvm/tools/llvm-c-test/include-all.c
@@ -37,7 +37,6 @@
 #include "llvm-c/TargetMachine.h"
 #include "llvm-c/Transforms/InstCombine.h"
 #include "llvm-c/Transforms/IPO.h"
-#include "llvm-c/Transforms/PassManagerBuilder.h"
 #include "llvm-c/Transforms/Scalar.h"
 #include "llvm-c/Transforms/Utils.h"
 #include "llvm-c/Transforms/Vectorize.h"