diff --git a/include/dbghelp.h b/include/dbghelp.h
index 1d3c8a6..734af15 100644
--- a/include/dbghelp.h
+++ b/include/dbghelp.h
@@ -614,7 +614,7 @@
 BOOL    WINAPI SymGetModuleInfoW(HANDLE, DWORD, PIMAGEHLP_MODULEW);
 DWORD   WINAPI SymGetModuleBase(HANDLE, DWORD);
 DWORD   WINAPI SymLoadModule(HANDLE, HANDLE, PSTR, PSTR, DWORD, DWORD);
-DWORD64 WINAPI SymLoadModuleEx(HANDLE, HANDLE, PSTR, PSTR, DWORD64, DWORD,
+DWORD64 WINAPI SymLoadModuleEx(HANDLE, HANDLE, PCSTR, PCSTR, DWORD64, DWORD,
                                PMODLOAD_DATA, DWORD);
 BOOL    WINAPI SymUnloadModule(HANDLE, DWORD);