Merge commit '6a1ea4ec932f4fc9fdc00ec51ee070b298ddb35f'

* commit '6a1ea4ec932f4fc9fdc00ec51ee070b298ddb35f':
  arm: warn/error on movrelx usage problematic with PIC on ELF

Merged-by: James Almer <jamrial@gmail.com>

libavutil/arm/asm.S

@@ -184,6 +184,15 @@ T       ldr             \rd, [\rd]
 .endm
 
 .macro  movrelx         rd,  val, gp
+    .ifc \rd,\gp
+        .error      "movrelx needs two distinct registers"
+    .endif
+    .ifc \rd\()_\gp,r12_
+        .warning    "movrelx rd=\rd without explicit set gp"
+    .endif
+    .ifc \rd\()_\gp,ip_
+        .warning    "movrelx rd=\rd without explicit set gp"
+    .endif
 #if CONFIG_PIC && defined(__ELF__)
     .ifnb \gp
       .if .Lpic_gp