[build] Fix undefined behavour sanitizer (#16375)

* [build] Fix integer overflow runtime error for core part

Temporarily remove circle ci UBSAN build precondition

* [build] Enable all of the ubsans

[build] Check runtime error

[build] Update UBSAN_OPTION

* [build] Add UBSAN blacklist

[build] Ignore system libraries

[build] Ignore vendor library

* [build] Fix implicit conversion runtime error in core

* [build] Fix division by zero runtime error

* [build] Add unfixed error to ubsan blacklist

* [build] Make UBSAN halt on error

Revert "Temporary remove build precondition"

* [build] Fix division by zero error

* [build] Make UBSAN officially work without FIXME prefix

* [build] Fix implicit conversion from int64_t to uint64_t

* [build] Rename style test json file name

* Address review findings

2 files changed, 4 insertions, 4 deletions

diff --git a/src/mbgl/util/premultiply.cpp b/src/mbgl/util/premultiply.cpp
index d9fb2480de..02c045fbb4 100644
--- a/src/mbgl/util/premultiply.cpp
+++ b/src/mbgl/util/premultiply.cpp
@@ -40,9 +40,9 @@ UnassociatedImage unpremultiply(PremultipliedImage&& src) {
         uint8_t& b = data[i + 2];
         uint8_t& a = data[i + 3];
         if (a) {
-            r = (255 * r + (a / 2)) / a;
-            g = (255 * g + (a / 2)) / a;
-            b = (255 * b + (a / 2)) / a;
+            r = static_cast<uint8_t>((255 * r + (a / 2)) / a);
+            g = static_cast<uint8_t>((255 * g + (a / 2)) / a);
+            b = static_cast<uint8_t>((255 * b + (a / 2)) / a);
         }
     }
 
diff --git a/src/mbgl/util/tiny_sdf.cpp b/src/mbgl/util/tiny_sdf.cpp
index 6edcd83bc2..a71d04386f 100644
--- a/src/mbgl/util/tiny_sdf.cpp
+++ b/src/mbgl/util/tiny_sdf.cpp
@@ -35,7 +35,7 @@ void edt1d(std::vector<double>& f,
 
     for (uint32_t q = 0, k = 0; q < n; q++) {
         while (z[k + 1] < q) k++;
-        d[q] = (q - v[k]) * (q - v[k]) + f[v[k]];
+        d[q] = (static_cast<double>(q) - v[k]) * (static_cast<double>(q) - v[k]) + f[v[k]];
     }
 }