commit ac304227bb3ea1787d581f17d76a5f5f3abff51f
Author: Rich Felker <dalias@aerifal.cx>
Date:   Wed May 22 18:28:32 2019 -0400

    make powerpc64 vrregset_t logical layout match expected API
    
    between v2 and v3 of the powerpc64 port patch, the change was made
    from a 32x4 array of 32-bit unsigned ints for vrregs[] to a 32-element
    array of __int128. this mismatches the API applications working with
    mcontext_t expect from glibc, and seems to have been motivated by a
    misinterpretation of a comment on how aarch64 did things as a
    suggestion to do the same on powerpc64.

diff --git a/arch/powerpc64/bits/signal.h b/arch/powerpc64/bits/signal.h
index 94c7a327..2cc0604c 100644
--- arch/powerpc64/bits/signal.h
+++ arch/powerpc64/bits/signal.h
@@ -16,7 +16,10 @@ typedef struct {
 } fpregset_t;
 
 typedef struct {
-	unsigned __int128 vrregs[32];
+#ifdef __GNUC__
+	__attribute__((__aligned__(16)))
+#endif
+	unsigned vrregs[32][4];
 	struct {
 #if __BIG_ENDIAN__
 		unsigned _pad[3], vscr_word;