diff --git a/libs/tiff/libtiff/tif_aux.c b/libs/tiff/libtiff/tif_aux.c
index ca033f64f2d..140f26c7df6 100644
--- a/libs/tiff/libtiff/tif_aux.c
+++ b/libs/tiff/libtiff/tif_aux.c
@@ -340,7 +340,7 @@ TIFFVGetFieldDefaulted(TIFF* tif, uint32_t tag, va_list ap)
  * Like TIFFGetField, but return any default
  * value if the tag is not present in the directory.
  */
-int WINAPIV
+int
 TIFFGetFieldDefaulted(TIFF* tif, uint32_t tag, ...)
 {
 	int ok;
diff --git a/libs/tiff/libtiff/tif_dir.c b/libs/tiff/libtiff/tif_dir.c
index 0bd43a62e74..a6c254fce27 100644
--- a/libs/tiff/libtiff/tif_dir.c
+++ b/libs/tiff/libtiff/tif_dir.c
@@ -824,7 +824,7 @@ OkToChangeTag(TIFF* tif, uint32_t tag)
  * when/if the directory structure is
  * updated.
  */
-int WINAPIV
+int
 TIFFSetField(TIFF* tif, uint32_t tag, ...)
 {
 	va_list ap;
@@ -1266,7 +1266,7 @@ _TIFFVGetField(TIFF* tif, uint32_t tag, va_list ap)
  * Return the value of a field in the
  * internal directory structure.
  */
-int WINAPIV
+int
 TIFFGetField(TIFF* tif, uint32_t tag, ...)
 {
 	int status;
diff --git a/libs/tiff/libtiff/tif_dirinfo.c b/libs/tiff/libtiff/tif_dirinfo.c
index 5d3a33810b1..8565dfbcebc 100644
--- a/libs/tiff/libtiff/tif_dirinfo.c
+++ b/libs/tiff/libtiff/tif_dirinfo.c
@@ -436,7 +436,7 @@ _TIFFSetupFields(TIFF* tif, const TIFFFieldArray* fieldarray)
 	}
 }
 
-static int  __cdecl
+static int
 tagCompare(const void* a, const void* b)
 {
 	const TIFFField* ta = *(const TIFFField**) a;
diff --git a/libs/tiff/libtiff/tif_error.c b/libs/tiff/libtiff/tif_error.c
index 9e0cb82f7dc..651168f7dc7 100644
--- a/libs/tiff/libtiff/tif_error.c
+++ b/libs/tiff/libtiff/tif_error.c
@@ -45,7 +45,7 @@ TIFFSetErrorHandlerExt(TIFFErrorHandlerExt handler)
 	return (prev);
 }
 
-void WINAPIV
+void
 TIFFError(const char* module, const char* fmt, ...)
 {
 	va_list ap;
@@ -61,7 +61,7 @@ TIFFError(const char* module, const char* fmt, ...)
 	}
 }
 
-void WINAPIV
+void
 TIFFErrorExt(thandle_t fd, const char* module, const char* fmt, ...)
 {
 	va_list ap;
diff --git a/libs/tiff/libtiff/tif_warning.c b/libs/tiff/libtiff/tif_warning.c
index 8bba83da67d..c482785c293 100644
--- a/libs/tiff/libtiff/tif_warning.c
+++ b/libs/tiff/libtiff/tif_warning.c
@@ -45,7 +45,7 @@ TIFFSetWarningHandlerExt(TIFFErrorHandlerExt handler)
 	return (prev);
 }
 
-void WINAPIV
+void
 TIFFWarning(const char* module, const char* fmt, ...)
 {
 	va_list ap;
@@ -61,7 +61,7 @@ TIFFWarning(const char* module, const char* fmt, ...)
 	}
 }
 
-void WINAPIV
+void
 TIFFWarningExt(thandle_t fd, const char* module, const char* fmt, ...)
 {
 	va_list ap;
diff --git a/libs/tiff/libtiff/tiffio.h b/libs/tiff/libtiff/tiffio.h
index 0212968b0c2..c6a192c5b3a 100644
--- a/libs/tiff/libtiff/tiffio.h
+++ b/libs/tiff/libtiff/tiffio.h
@@ -347,9 +347,9 @@ extern void TIFFCleanup(TIFF* tif);
 extern void TIFFClose(TIFF* tif);
 extern int TIFFFlush(TIFF* tif);
 extern int TIFFFlushData(TIFF* tif);
-extern int WINAPIV TIFFGetField(TIFF* tif, uint32_t tag, ...);
+extern int TIFFGetField(TIFF* tif, uint32_t tag, ...);
 extern int TIFFVGetField(TIFF* tif, uint32_t tag, va_list ap);
-extern int WINAPIV TIFFGetFieldDefaulted(TIFF* tif, uint32_t tag, ...);
+extern int TIFFGetFieldDefaulted(TIFF* tif, uint32_t tag, ...);
 extern int TIFFVGetFieldDefaulted(TIFF* tif, uint32_t tag, va_list ap);
 extern int TIFFReadDirectory(TIFF* tif);
 extern int TIFFReadCustomDirectory(TIFF* tif, toff_t diroff, const TIFFFieldArray* infoarray);
@@ -410,7 +410,7 @@ extern int TIFFLastDirectory(TIFF*);
 extern int TIFFSetDirectory(TIFF*, uint16_t);
 extern int TIFFSetSubDirectory(TIFF*, uint64_t);
 extern int TIFFUnlinkDirectory(TIFF*, uint16_t);
-extern int WINAPIV TIFFSetField(TIFF*, uint32_t, ...);
+extern int TIFFSetField(TIFF*, uint32_t, ...);
 extern int TIFFVSetField(TIFF*, uint32_t, va_list);
 extern int TIFFUnsetField(TIFF*, uint32_t);
 extern int TIFFWriteDirectory(TIFF *);
@@ -456,10 +456,10 @@ extern TIFF* TIFFClientOpen(const char*, const char*,
 	    TIFFMapFileProc, TIFFUnmapFileProc);
 extern const char* TIFFFileName(TIFF*);
 extern const char* TIFFSetFileName(TIFF*, const char *);
-extern void WINAPIV TIFFError(const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,2,3)));
-extern void WINAPIV TIFFErrorExt(thandle_t, const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,3,4)));
-extern void WINAPIV TIFFWarning(const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,2,3)));
-extern void WINAPIV TIFFWarningExt(thandle_t, const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,3,4)));
+extern void TIFFError(const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,2,3)));
+extern void TIFFErrorExt(thandle_t, const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,3,4)));
+extern void TIFFWarning(const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,2,3)));
+extern void TIFFWarningExt(thandle_t, const char*, const char*, ...) TIFF_ATTRIBUTE((__format__ (__printf__,3,4)));
 extern TIFFErrorHandler TIFFSetErrorHandler(TIFFErrorHandler);
 extern TIFFErrorHandlerExt TIFFSetErrorHandlerExt(TIFFErrorHandlerExt);
 extern TIFFErrorHandler TIFFSetWarningHandler(TIFFErrorHandler);