Upstream: Should be
Reason: Fixes compilation with gcc-10

diff --git a/src/via_driver.h b/src/via_driver.h
index a1ad2f5..173e86e 100644
--- a/src/via_driver.h
+++ b/src/via_driver.h
@@ -394,8 +394,8 @@ typedef struct
 
 
 /* In via_display.c. */
-const xf86CrtcFuncsRec iga1_crtc_funcs;
-const xf86CrtcFuncsRec iga2_crtc_funcs;
+extern const xf86CrtcFuncsRec iga1_crtc_funcs;
+extern const xf86CrtcFuncsRec iga2_crtc_funcs;
 
 /* In via_exa.c. */
 Bool viaInitExa(ScreenPtr pScreen);
diff --git a/src/via_vt1632.h b/src/via_vt1632.h
index 41df77f..8415fae 100644
--- a/src/via_vt1632.h
+++ b/src/via_vt1632.h
@@ -44,7 +44,7 @@ typedef struct _viaVT1632Rec {
 } viaVT1632Rec, *viaVT1632RecPtr;
 
 
-const xf86OutputFuncsRec via_vt1632_funcs;
+extern const xf86OutputFuncsRec via_vt1632_funcs;
 
 Bool viaVT1632Init(ScrnInfoPtr pScrn, I2CBusPtr pI2CBus);
 
diff --git a/src/via_sii164.h b/src/via_sii164.h
index 10077a3..f7f3a4f 100644
--- a/src/via_sii164.h
+++ b/src/via_sii164.h
@@ -47,7 +47,7 @@ typedef struct _viaSiI164 {
 } viaSiI164Rec, *viaSiI164RecPtr;
 
 
-const xf86OutputFuncsRec via_sii164_funcs;
+extern const xf86OutputFuncsRec via_sii164_funcs;
 
 Bool viaSiI164Init(ScrnInfoPtr pScrn, I2CBusPtr pI2CBus);