diff --git a/recompiler/src/recompiler_patch.cpp b/recompiler/src/recompiler_patch.cpp
index f6741509..31b15bb9 100644
--- a/recompiler/src/recompiler_patch.cpp
+++ b/recompiler/src/recompiler_patch.cpp
@@ -23,10 +23,6 @@ uint32_t apply_one_recompiler_patch(const RecompilerPatch& patch,
 
 } // namespace
 
-uint32_t recompiler_patch_address_key(uint32_t address) {
-    return address & 0x1FFFFFFFu;
-}
-
 uint32_t apply_recompiler_patch(const std::vector<RecompilerPatch>& patches,
                                 uint32_t address,
                                 uint32_t observed,
diff --git a/recompiler/src/recompiler_patch.h b/recompiler/src/recompiler_patch.h
index afb29cba..472af983 100644
--- a/recompiler/src/recompiler_patch.h
+++ b/recompiler/src/recompiler_patch.h
@@ -21,7 +21,9 @@ struct RecompilerPatch {
     std::string note;
 };
 
-uint32_t recompiler_patch_address_key(uint32_t address);
+inline uint32_t recompiler_patch_address_key(uint32_t address) {
+    return address & 0x1FFFFFFFu;
+}
 
 // Apply the patch targeting address, if any. A main-EXE guard mismatch throws;
 // an overlay mismatch is an expected different variant and leaves the observed
diff --git a/recompiler/tests/recompiler_patch_cxx17_header_test.cpp b/recompiler/tests/recompiler_patch_cxx17_header_test.cpp
index 70a1ea85..048bda43 100644
--- a/recompiler/tests/recompiler_patch_cxx17_header_test.cpp
+++ b/recompiler/tests/recompiler_patch_cxx17_header_test.cpp
@@ -5,5 +5,9 @@
 int main() {
     std::vector<PSXRecompV4::RecompilerPatch> patches;
     patches.push_back({"header-smoke", 0x80010000u, 0u, 0u, {}});
-    return patches.front().id == "header-smoke" ? 0 : 1;
+    return patches.front().id == "header-smoke" &&
+                   PSXRecompV4::recompiler_patch_address_key(
+                       patches.front().address) == 0x00010000u
+               ? 0
+               : 1;
 }