add asan option to build to help fix memory issues (foreshadowing); remove unnecessary contains check on node_tag_map; replace strcpy with memcpy on SimplifyResult::asString since we're not working with null-terminated strings (huge memory issue)

Author: TechHog8984

build.sh

@@ -9,6 +9,7 @@ LUAU_INCLUDE_BUILD=$(echo $LUAU_INCLUDE | sed 's/dependencies\//..\/..\/..\/depe
 PLATFORM=linux
 RELEASE_FLAGS=
 STATIC_FLAGS=-static
+ASAN_FLAGS=
 TEST_DEFINES=
 
 while [[ $# -gt 0 ]]; do
@@ -37,6 +38,10 @@ while [[ $# -gt 0 ]]; do
             TEST_DEFINES=-DFAILTESTS
             shift
             ;;
+        --asan)
+            ASAN_FLAGS=-fsanitize=address
+            shift
+            ;;
         *)
             echo "Unknown option: $1"
             exit 1
@@ -94,7 +99,7 @@ mkdir $luauformatbuilddir
 
 echo "building luau-format..."
 pushd $luauformatbuilddir
-$compiler -std=c++17 -g -Wall $RELEASE_FLAGS -c ../../../src/* -I../../../include $LUAU_INCLUDE_BUILD -L../Luau -lluau
+$compiler -std=c++17 -g -Wall $RELEASE_FLAGS $ASAN_FLAGS -c ../../../src/* -I../../../include $LUAU_INCLUDE_BUILD -L../Luau -lluau
 ar rcs libluau-format.a *.o
 popd
 echo "luau-format built"
@@ -104,11 +109,11 @@ if [[ $TEST ]]; then
     if [[ ! $TEST_DEFINES = "" ]]; then
         echo "NOTE: tests will fail due to --failtests being passed"
     fi
-    $compiler -std=c++17 $STATIC_FLAGS -o $outfile -g -Wall tests/* -Itests -Iinclude $LUAU_INCLUDE $TEST_DEFINES -L$luauformatbuilddir -lluau-format -L$luaubuilddir -lluau
+    $compiler -std=c++17 $ASAN_FLAGS $STATIC_FLAGS -o $outfile -g -Wall tests/* -Itests -Iinclude $LUAU_INCLUDE $TEST_DEFINES -L$luauformatbuilddir -lluau-format -L$luaubuilddir -lluau
     echo "tests built to $outfile"
     exit
 fi
 
 echo "buildling cli..."
-$compiler -std=c++17 -g -Wall $RELEASE_FLAGS $STATIC_FLAGS -o $outfile main.cpp -Iinclude $LUAU_INCLUDE -L$luauformatbuilddir -lluau-format -L$luaubuilddir -lluau
+$compiler -std=c++17 -g -Wall $RELEASE_FLAGS $ASAN_FLAGS $STATIC_FLAGS -o $outfile main.cpp -Iinclude $LUAU_INCLUDE -L$luauformatbuilddir -lluau-format -L$luaubuilddir -lluau
 echo "cli built to $outfile"

src/formatter.cpp

@@ -349,8 +349,7 @@ size_t AstFormatter::appendOptionalSemicolon(std::string& current, std::string&
 }
 
 AstFormatter::NodeTag& AstFormatter::getNodeTag(AstNode* node) {
-    if (node_tag_map.find(node) == node_tag_map.end())
-        node_tag_map.emplace(node, NodeTag{});
+    node_tag_map.emplace(node, NodeTag{});
 
     return node_tag_map.at(node);
 }

src/simplifier.cpp

@@ -1269,10 +1269,11 @@ std::optional<AstArray<char>> SimplifyResult::asString() {
     switch (type) {
         case Number: {
             std::string str = convertNumber(number_value);
-            char* allocated = static_cast<char*>(simplifier->getAllocator().allocate(str.size()));
-            strcpy(allocated, str.data());
+            const size_t len = str.size();
+            char* allocated = static_cast<char*>(simplifier->getAllocator().allocate(len));
+            memcpy(allocated, str.data(), len);
             result.data = allocated;
-            result.size = str.size();
+            result.size = len;
             return result;
         }
         default: