libswscale/swscale.c:1064: error: Uninitialized Value
  The value read from A1 was never initialized.

libswscale/swscale.c:1064:40: 
1062.         b =  c->table_bU[U];
1063. 
1064.         yuv2rgb_write(dest, i, Y1, Y2, hasAlpha ? A1 : 0, hasAlpha ? A2 : 0,
                                             ^
1065.                       r, g, b, y, target, hasAlpha);
1066.     }

static av_always_inline void
yuv2rgb_X_c_template(SwsContext *c, const int16_t *lumFilter,
                     const int16_t **lumSrc, int lumFilterSize,
                     const int16_t *chrFilter, const int16_t **chrUSrc,
                     const int16_t **chrVSrc, int chrFilterSize,
                     const int16_t **alpSrc, uint8_t *dest, int dstW,
                     int y, enum PixelFormat target, int hasAlpha)
{
    int i;
    for (i = 0; i < (dstW >> 1); i++) {
        int j;
        int Y1 = 1 << 18;
        int Y2 = 1 << 18;
        int U  = 1 << 18;
        int V  = 1 << 18;
        int av_unused A1, A2;
        const void *r, *g, *b;
        for (j = 0; j < lumFilterSize; j++) {
            Y1 += lumSrc[j][i * 2]     * lumFilter[j];
            Y2 += lumSrc[j][i * 2 + 1] * lumFilter[j];
        }
        for (j = 0; j < chrFilterSize; j++) {
            U += chrUSrc[j][i] * chrFilter[j];
            V += chrVSrc[j][i] * chrFilter[j];
        }
        Y1 >>= 19;
        Y2 >>= 19;
        U  >>= 19;
        V  >>= 19;
        if ((Y1 | Y2 | U | V) & 0x100) {
            Y1 = av_clip_uint8(Y1);
            Y2 = av_clip_uint8(Y2);
            U  = av_clip_uint8(U);
            V  = av_clip_uint8(V);
        }
        if (hasAlpha) {
            A1 = 1 << 18;
            A2 = 1 << 18;
            for (j = 0; j < lumFilterSize; j++) {
                A1 += alpSrc[j][i * 2    ] * lumFilter[j];
                A2 += alpSrc[j][i * 2 + 1] * lumFilter[j];
            }
            A1 >>= 19;
            A2 >>= 19;
            if ((A1 | A2) & 0x100) {
                A1 = av_clip_uint8(A1);
                A2 = av_clip_uint8(A2);
            }
        }
        r =  c->table_rV[V];
        g = (c->table_gU[U] + c->table_gV[V]);
        b =  c->table_bU[U];
        yuv2rgb_write(dest, i, Y1, Y2, hasAlpha ? A1 : 0, hasAlpha ? A2 : 0,
                      r, g, b, y, target, hasAlpha);
    }
}
['static av_always_inline void\nyuv2rgb_X_c_template(SwsContext *c, const int16_t *lumFilter,\n                     const int16_t **lumSrc, int lumFilterSize,\n                     const int16_t *chrFilter, const int16_t **chrUSrc,\n                     const int16_t **chrVSrc, int chrFilterSize,\n                     const int16_t **alpSrc, uint8_t *dest, int dstW,\n                     int y, enum PixelFormat target, int hasAlpha)\n{\n    int i;\n    for (i = 0; i < (dstW >> 1); i++) {\n        int j;\n        int Y1 = 1 << 18;\n        int Y2 = 1 << 18;\n        int U  = 1 << 18;\n        int V  = 1 << 18;\n        int av_unused A1, A2;\n        const void *r, *g, *b;\n        for (j = 0; j < lumFilterSize; j++) {\n            Y1 += lumSrc[j][i * 2]     * lumFilter[j];\n            Y2 += lumSrc[j][i * 2 + 1] * lumFilter[j];\n        }\n        for (j = 0; j < chrFilterSize; j++) {\n            U += chrUSrc[j][i] * chrFilter[j];\n            V += chrVSrc[j][i] * chrFilter[j];\n        }\n        Y1 >>= 19;\n        Y2 >>= 19;\n        U  >>= 19;\n        V  >>= 19;\n        if ((Y1 | Y2 | U | V) & 0x100) {\n            Y1 = av_clip_uint8(Y1);\n            Y2 = av_clip_uint8(Y2);\n            U  = av_clip_uint8(U);\n            V  = av_clip_uint8(V);\n        }\n        if (hasAlpha) {\n            A1 = 1 << 18;\n            A2 = 1 << 18;\n            for (j = 0; j < lumFilterSize; j++) {\n                A1 += alpSrc[j][i * 2    ] * lumFilter[j];\n                A2 += alpSrc[j][i * 2 + 1] * lumFilter[j];\n            }\n            A1 >>= 19;\n            A2 >>= 19;\n            if ((A1 | A2) & 0x100) {\n                A1 = av_clip_uint8(A1);\n                A2 = av_clip_uint8(A2);\n            }\n        }\n        r =  c->table_rV[V];\n        g = (c->table_gU[U] + c->table_gV[V]);\n        b =  c->table_bU[U];\n        yuv2rgb_write(dest, i, Y1, Y2, hasAlpha ? A1 : 0, hasAlpha ? A2 : 0,\n                      r, g, b, y, target, hasAlpha);\n    }\n}']