Fixed spurious warning about old-style prototype.

[BearSSL] / src / int / i15_mulacc.c

diff --git a/src/int/i15_mulacc.c b/src/int/i15_mulacc.c
index 7bde395..7a073ac 100644 (file)
--- a/src/int/i15_mulacc.c
+++ b/src/int/i15_mulacc.c
@@ -29,10 +29,19 @@ void
 br_i15_mulacc(uint16_t *d, const uint16_t *a, const uint16_t *b)
 {
        size_t alen, blen, u;
+       unsigned dl, dh;
 
        alen = (a[0] + 15) >> 4;
        blen = (b[0] + 15) >> 4;
-       d[0] = a[0] + b[0];
+
+       /*
+        * Announced bit length of d[] will be the sum of the announced
+        * bit lengths of a[] and b[]; but the lengths are encoded.
+        */
+       dl = (a[0] & 15) + (b[0] & 15);
+       dh = (a[0] >> 4) + (b[0] >> 4);
+       d[0] = (dh << 4) + dl + (~(uint32_t)(dl - 15) >> 31);
+
        for (u = 0; u < blen; u ++) {
                uint32_t f;
                size_t v;