Fix fuzzer's bools to be 0 or 1 only

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2447823002

Review-Url: https://codereview.chromium.org/2447823002

1 files changed, 12 insertions, 0 deletions

diff --git a/fuzz/Fuzz.h b/fuzz/Fuzz.h
index 0ab3c1bc6e..c9c21567a5 100644
--- a/fuzz/Fuzz.h
+++ b/fuzz/Fuzz.h
@@ -24,6 +24,18 @@ public:
     template <typename T>
     bool next(T* n);
 
+    // UBSAN reminds us that bool can only legally hold 0 or 1.
+    bool next(bool* b) {
+        uint8_t byte;
+        if (!this->next(&byte)) {
+            return false;
+        }
+        *b = (byte & 1) == 1;
+        return true;
+    }
+
+    // The nextFoo methods are deprecated.
+    // TODO(kjlubick): replace existing uses with next() and remove these.
     bool nextBool();
     uint8_t  nextB();
     uint32_t nextU();