diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index db044878fe7..5cb7215a198 100644
--- a/src/librustc_codegen_llvm/back/write.rs
+++ b/src/librustc_codegen_llvm/back/write.rs
@@ -541,11 +541,23 @@ unsafe fn optimize(cgcx: &CodegenContext,
             };
 
             if config.verify_llvm_ir { assert!(addpass("verify")); }
+
+            // Some options cause LLVM bitcode to be emitted, which uses ThinLTOBuffers, so we need
+            // to make sure we run LLVM's NameAnonGlobals pass when emitting bitcode; otherwise
+            // we'll get errors in LLVM.
+            let using_thin_buffers = llvm::LLVMRustThinLTOAvailable() && (config.emit_bc
+                || config.obj_is_bitcode || config.emit_bc_compressed || config.embed_bitcode);
+            let mut have_name_anon_globals_pass = false;
             if !config.no_prepopulate_passes {
                 llvm::LLVMRustAddAnalysisPasses(tm, fpm, llmod);
                 llvm::LLVMRustAddAnalysisPasses(tm, mpm, llmod);
                 let opt_level = config.opt_level.unwrap_or(llvm::CodeGenOptLevel::None);
                 let prepare_for_thin_lto = cgcx.lto == Lto::Thin || cgcx.lto == Lto::ThinLocal;
+                have_name_anon_globals_pass = have_name_anon_globals_pass || prepare_for_thin_lto;
+                if using_thin_buffers && !prepare_for_thin_lto {
+                    assert!(addpass("name-anon-globals"));
+                    have_name_anon_globals_pass = true;
+                }
                 with_llvm_pmb(llmod, &config, opt_level, prepare_for_thin_lto, &mut |b| {
                     llvm::LLVMPassManagerBuilderPopulateFunctionPassManager(b, fpm);
                     llvm::LLVMPassManagerBuilderPopulateModulePassManager(b, mpm);
@@ -557,6 +569,9 @@ unsafe fn optimize(cgcx: &CodegenContext,
                     diag_handler.warn(&format!("unknown pass `{}`, ignoring",
                                             pass));
                 }
+                if pass == "name-anon-globals" {
+                    have_name_anon_globals_pass = true;
+                }
             }
 
             for pass in &cgcx.plugin_passes {
@@ -565,6 +580,22 @@ unsafe fn optimize(cgcx: &CodegenContext,
                                             `{}` but LLVM does not \
                                             recognize it", pass));
                 }
+                if pass == "name-anon-globals" {
+                    have_name_anon_globals_pass = true;
+                }
+            }
+
+            if using_thin_buffers && !have_name_anon_globals_pass {
+                // As described above, this will probably cause an error in LLVM
+                if config.no_prepopulate_passes {
+                    diag_handler.err("The current compilation is going to use thin LTO buffers \
+                                     without running LLVM's NameAnonGlobals pass. \
+                                     This will likely cause errors in LLVM. Consider adding \
+                                     -C passes=name-anon-globals to the compiler command line.");
+                } else {
+                    bug!("We are using thin LTO buffers without running the NameAnonGlobals pass. \
+                         This will likely cause errors in LLVM and shoud never happen.");
+                }
             }
         }
 
diff --git a/src/test/run-pass-fulldeps/myriad-closures.rs b/src/test/run-pass-fulldeps/myriad-closures.rs
index a946ec635b2..baf27d6f57c 100644
--- a/src/test/run-pass-fulldeps/myriad-closures.rs
+++ b/src/test/run-pass-fulldeps/myriad-closures.rs
@@ -14,7 +14,7 @@
 // See https://github.com/rust-lang/rust/issues/34793 for more information.
 
 // Make sure we don't optimize anything away:
-// compile-flags: -C no-prepopulate-passes
+// compile-flags: -C no-prepopulate-passes -Cpasses=name-anon-globals
 
 // Expand something exponentially
 macro_rules! go_bacterial {
diff --git a/src/test/run-pass/issue-38226.rs b/src/test/run-pass/issue-38226.rs
index 33604212af9..dd9f9be7da7 100644
--- a/src/test/run-pass/issue-38226.rs
+++ b/src/test/run-pass/issue-38226.rs
@@ -15,7 +15,7 @@
 
 // Need -Cno-prepopulate-passes to really disable inlining, otherwise the faulty
 // code gets optimized out:
-// compile-flags: -Cno-prepopulate-passes
+// compile-flags: -Cno-prepopulate-passes -Cpasses=name-anon-globals
 
 extern crate issue_38226_aux;
 
diff --git a/src/test/ui/feature-gate-unwind-attributes.rs b/src/test/ui/feature-gate-unwind-attributes.rs
index c8f9cd943cd..681842e30e0 100644
--- a/src/test/ui/feature-gate-unwind-attributes.rs
+++ b/src/test/ui/feature-gate-unwind-attributes.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -C no-prepopulate-passes
+// compile-flags: -C no-prepopulate-passes -Cpasses=name-anon-globals
 
 #![crate_type = "lib"]