diff --git a/libraries/chain/CMakeLists.txt b/libraries/chain/CMakeLists.txt
index a0d6525143..242132824c 100644
--- a/libraries/chain/CMakeLists.txt
+++ b/libraries/chain/CMakeLists.txt
@@ -34,11 +34,16 @@ if("eos-vm-oc" IN_LIST EOSIO_WASM_RUNTIMES)
                              webassembly/runtimes/eos-vm-oc.cpp
                              webassembly/runtimes/eos-vm-oc/default_real_main.cpp)
 
+   set_source_files_properties(webassembly/runtimes/eos-vm-oc/LLVMJIT.cpp PROPERTIES COMPILE_FLAGS "--std=gnu++17")
+   set_source_files_properties(webassembly/runtimes/eos-vm-oc/LLVMEmitIR.cpp PROPERTIES COMPILE_FLAGS "--std=gnu++17")
+
    if(LLVM_VERSION VERSION_LESS 7.1 AND CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
       enable_language(ASM-LLVMWAR)
       list(APPEND CHAIN_EOSVMOC_SOURCES webassembly/runtimes/eos-vm-oc/llvmWARshim.llvmwar)
+      set_source_files_properties(webassembly/runtimes/eos-vm-oc/llvmWARshim.llvmwar PROPERTIES COMPILE_FLAGS "--std=gnu++17")
    else()
       list(APPEND CHAIN_EOSVMOC_SOURCES webassembly/runtimes/eos-vm-oc/llvmWARshim.cpp)
+      set_source_files_properties(webassembly/runtimes/eos-vm-oc/llvmWARshim.cpp PROPERTIES COMPILE_FLAGS "--std=gnu++17")
    endif()
 
    llvm_map_components_to_libnames(LLVM_LIBS support core passes mcjit native orcjit)
diff --git a/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMEmitIR.h b/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMEmitIR.h
new file mode 100644
index 0000000000..2451603a77
--- /dev/null
+++ b/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMEmitIR.h
@@ -0,0 +1,18 @@
+#pragma once
+
+#include "Inline/BasicTypes.h"
+#include "IR/Module.h"
+
+#include "llvm/IR/Module.h"
+
+#include <vector>
+#include <map>
+
+namespace eosio { namespace chain { namespace eosvmoc {
+
+namespace LLVMJIT {
+   bool getFunctionIndexFromExternalName(const char* externalName,Uptr& outFunctionDefIndex);
+   const char* getTableSymbolName();
+   llvm::Module* emitModule(const IR::Module& module);
+}
+}}}
diff --git a/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.cpp b/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.cpp
index 8b76b715af..f1eca8073d 100644
--- a/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.cpp
+++ b/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.cpp
@@ -15,6 +15,7 @@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 */
 
 #include "LLVMJIT.h"
+#include "LLVMEmitIR.h"
 
 #include "llvm/ExecutionEngine/ExecutionEngine.h"
 #include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
@@ -39,6 +40,7 @@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Object/SymbolSize.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/DataExtractor.h"
 #include "llvm/Support/DataTypes.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/TargetSelect.h"
@@ -49,10 +51,7 @@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 #include "llvm/Transforms/InstCombine/InstCombine.h"
 #include "llvm/Transforms/Utils.h"
 #include <memory>
-
-#include <fc/io/datastream.hpp>
-#include <fc/io/raw.hpp>
-#include <fc/reflect/typename.hpp>
+#include <unistd.h>
 
 #include "llvm/Support/LEB128.h"
 
@@ -151,7 +150,7 @@ namespace LLVMJIT
 		std::list<std::vector<uint8_t>> stack_sizes;
 
 		U8* get_next_code_ptr(uintptr_t numBytes, U32 alignment) {
-			FC_ASSERT(alignment <= alignof(std::max_align_t), "alignment of section exceeds max_align_t");
+			WAVM_ASSERT_THROW(alignment <= alignof(std::max_align_t));
 			uintptr_t p = (uintptr_t)ptr;
 			p += alignment - 1LL;
 			p &= ~(alignment - 1LL);
@@ -306,12 +305,14 @@ namespace LLVMJIT
 
 		unsigned num_functions_stack_size_found = 0;
 		for(const auto& stacksizes : jitModule->unitmemorymanager->stack_sizes) {
-			fc::datastream<const char*> ds(reinterpret_cast<const char*>(stacksizes.data()), stacksizes.size());
-			while(ds.remaining()) {
-				uint64_t funcaddr;
-				fc::unsigned_int stack_size;
-				fc::raw::unpack(ds, funcaddr);
-				fc::raw::unpack(ds, stack_size);
+			llvm::DataExtractor ds(llvm::ArrayRef(stacksizes.data(), stacksizes.size()), true, 8);
+			llvm::DataExtractor::Cursor c(0);
+
+			while(!ds.eof(c)) {
+				ds.getAddress(c);
+				WAVM_ASSERT_THROW(!!c);
+				const uint64_t stack_size = ds.getULEB128(c);
+				WAVM_ASSERT_THROW(!!c);
 
 				++num_functions_stack_size_found;
 				if(stack_size > 16u*1024u)
diff --git a/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.h b/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.h
index 4d5a685c29..13e2510195 100644
--- a/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.h
+++ b/libraries/chain/webassembly/runtimes/eos-vm-oc/LLVMJIT.h
@@ -3,10 +3,6 @@
 #include "Inline/BasicTypes.h"
 #include "IR/Module.h"
 
-#pragma push_macro("N")
-#undef N
-#include "llvm/IR/Module.h"
-#pragma pop_macro("N")
 #include <vector>
 #include <map>
 
@@ -19,9 +15,6 @@ struct instantiated_code {
 };
 
 namespace LLVMJIT {
-   bool getFunctionIndexFromExternalName(const char* externalName,Uptr& outFunctionDefIndex);
-   const char* getTableSymbolName();
-   llvm::Module* emitModule(const IR::Module& module);
    instantiated_code instantiateModule(const IR::Module& module);
 }
 }}}