diff --git a/Ghidra/Processors/x86/data/languages/x86gcc.cspec b/Ghidra/Processors/x86/data/languages/x86gcc.cspec
index 17448cf9..b115b957 100644
--- a/Ghidra/Processors/x86/data/languages/x86gcc.cspec
+++ b/Ghidra/Processors/x86/data/languages/x86gcc.cspec
@@ -286,6 +286,40 @@
       <register name="EAX"/>
     </killedbycall>
   </prototype>
+  <prototype name="__stdcall" extrapop="unknown" stackshift="4">
+    <input>
+      <pentry minsize="1" maxsize="500" align="4">
+        <addr offset="4" space="stack"/>
+      </pentry>
+    </input>
+    <output killedbycall="true">
+      <pentry minsize="4" maxsize="10" metatype="float" extension="float">
+        <register name="ST0"/>
+      </pentry>
+      <pentry minsize="1" maxsize="4">
+        <register name="EAX"/>
+      </pentry>
+      <pentry minsize="5" maxsize="8">
+        <addr space="join" piece1="EDX" piece2="EAX"/>
+      </pentry>
+    </output>
+    <unaffected>
+      <register name="ESP"/>
+      <register name="EBP"/>
+      <register name="ESI"/>
+      <register name="EDI"/>
+      <register name="EBX"/>
+    </unaffected>
+    <killedbycall>
+      <register name="ECX"/>
+      <register name="EDX"/>
+      <register name="ST0"/>
+      <register name="ST1"/>
+    </killedbycall>
+    <likelytrash>
+      <register name="EAX"/>
+    </likelytrash>
+  </prototype>
   
   <resolveprototype name="__cdecl/__regparm">
     <model name="__cdecl"/>        <!-- The default case -->