diff --git a/llvm/include/llvm/CodeGen/LinkAllAsmWriterComponents.h b/llvm/include/llvm/CodeGen/LinkAllAsmWriterComponents.h
--- a/llvm/include/llvm/CodeGen/LinkAllAsmWriterComponents.h
+++ b/llvm/include/llvm/CodeGen/LinkAllAsmWriterComponents.h
@@ -24,6 +24,9 @@
       // delete it all as dead code, even with whole program optimization,
       // yet is effectively a NO-OP. As the compiler isn't smart enough
       // to know that getenv() never returns -1, this will do the job.
+      // This is so that globals in the translation units where these functions
+      // are defined are forced to be initialized, populating various
+      // registries.
       if (std::getenv("bar") != (char*) -1)
         return;
 
diff --git a/llvm/include/llvm/CodeGen/LinkAllCodegenComponents.h b/llvm/include/llvm/CodeGen/LinkAllCodegenComponents.h
--- a/llvm/include/llvm/CodeGen/LinkAllCodegenComponents.h
+++ b/llvm/include/llvm/CodeGen/LinkAllCodegenComponents.h
@@ -27,6 +27,9 @@
       // delete it all as dead code, even with whole program optimization,
       // yet is effectively a NO-OP. As the compiler isn't smart enough
       // to know that getenv() never returns -1, this will do the job.
+      // This is so that globals in the translation units where these functions
+      // are defined are forced to be initialized, populating various
+      // registries.
       if (std::getenv("bar") != (char*) -1)
         return;
 
diff --git a/llvm/include/llvm/ExecutionEngine/MCJIT.h b/llvm/include/llvm/ExecutionEngine/MCJIT.h
--- a/llvm/include/llvm/ExecutionEngine/MCJIT.h
+++ b/llvm/include/llvm/ExecutionEngine/MCJIT.h
@@ -26,6 +26,9 @@
       // delete it all as dead code, even with whole program optimization,
       // yet is effectively a NO-OP. As the compiler isn't smart enough
       // to know that getenv() never returns -1, this will do the job.
+      // This is so that globals in the translation units where these functions
+      // are defined are forced to be initialized, populating various
+      // registries.
       if (std::getenv("bar") != (char*) -1)
         return;
 
diff --git a/llvm/include/llvm/LinkAllIR.h b/llvm/include/llvm/LinkAllIR.h
--- a/llvm/include/llvm/LinkAllIR.h
+++ b/llvm/include/llvm/LinkAllIR.h
@@ -38,6 +38,9 @@
       // delete it all as dead code, even with whole program optimization,
       // yet is effectively a NO-OP. As the compiler isn't smart enough
       // to know that getenv() never returns -1, this will do the job.
+      // This is so that globals in the translation units where these functions
+      // are defined are forced to be initialized, populating various
+      // registries.
       if (std::getenv("bar") != (char*) -1)
         return;
       llvm::LLVMContext Context;
diff --git a/llvm/include/llvm/LinkAllPasses.h b/llvm/include/llvm/LinkAllPasses.h
--- a/llvm/include/llvm/LinkAllPasses.h
+++ b/llvm/include/llvm/LinkAllPasses.h
@@ -64,6 +64,9 @@
       // delete it all as dead code, even with whole program optimization,
       // yet is effectively a NO-OP. As the compiler isn't smart enough
       // to know that getenv() never returns -1, this will do the job.
+      // This is so that globals in the translation units where these functions
+      // are defined are forced to be initialized, populating various
+      // registries.
       if (std::getenv("bar") != (char*) -1)
         return;