diff --git a/src/backend_x64/emit_x64.cpp b/src/backend_x64/emit_x64.cpp
index cd01bbb3..8a46f7d8 100644
--- a/src/backend_x64/emit_x64.cpp
+++ b/src/backend_x64/emit_x64.cpp
@@ -361,11 +361,11 @@ void EmitX64::EmitPushRSB(IR::Block&, IR::Inst* inst) {
 }
 
 void EmitX64::EmitGetCarryFromOp(IR::Block&, IR::Inst*) {
-    ASSERT_MSG(0, "should never happen");
+    ASSERT_MSG(false, "should never happen");
 }
 
 void EmitX64::EmitGetOverflowFromOp(IR::Block&, IR::Inst*) {
-    ASSERT_MSG(0, "should never happen");
+    ASSERT_MSG(false, "should never happen");
 }
 
 void EmitX64::EmitPack2x32To1x64(IR::Block&, IR::Inst* inst) {
@@ -2002,7 +2002,7 @@ static Xbyak::Label EmitCond(BlockOfCode* code, Arm::Cond cond) {
         break;
     }
     default:
-        ASSERT_MSG(0, "Unknown cond %zu", static_cast<size_t>(cond));
+        ASSERT_MSG(false, "Unknown cond %zu", static_cast<size_t>(cond));
         break;
     }
 
@@ -2047,7 +2047,7 @@ void EmitX64::EmitTerminal(IR::Terminal terminal, Arm::LocationDescriptor initia
         EmitTerminalCheckHalt(boost::get<IR::Term::CheckHalt>(terminal), initial_location);
         return;
     default:
-        ASSERT_MSG(0, "Invalid Terminal. Bad programmer.");
+        ASSERT_MSG(false, "Invalid Terminal. Bad programmer.");
         return;
     }
 }
diff --git a/src/backend_x64/reg_alloc.cpp b/src/backend_x64/reg_alloc.cpp
index 66902fda..f7fed276 100644
--- a/src/backend_x64/reg_alloc.cpp
+++ b/src/backend_x64/reg_alloc.cpp
@@ -371,7 +371,7 @@ HostLoc RegAlloc::FindFreeSpill() const {
         if (!IsRegisterOccupied(HostLocSpill(i)))
             return HostLocSpill(i);
 
-    ASSERT_MSG(0, "All spill locations are full");
+    ASSERT_MSG(false, "All spill locations are full");
 }
 
 void RegAlloc::EndOfAllocScope() {
@@ -476,7 +476,7 @@ std::tuple<HostLoc, bool> RegAlloc::UseHostLoc(IR::Inst* use_inst, HostLocList d
         return std::make_tuple(new_location, false);
     }
 
-    ASSERT_MSG(0, "Invalid current_location");
+    ASSERT_MSG(false, "Invalid current_location");
     return std::make_tuple(static_cast<HostLoc>(-1), false);
 }