New Functionality

Control-flow-based optimizations enabled and expanded

We built out the control-flow-based optimization first introduced as an experimental feature in spicy-1.14, and with this release these optimizer passes are enabled by default. For that we made the framework more efficient and cleaned up issues in the implementation.

We also introduced a new pass performing constant propagation (GH-2137, GH-2150) and reducing nested scopes to simplify data flow analysis (GH-1425).
GH-2197: Support coercion from empty list to struct

Spicy struct fields can already be declared with a &default value to reduce data duplication. We now allow constructing struct values from empty lists [] which effectively allows default-construction.

Changed Functionality

GH-2183: Use dedicated C++ types for representing optional and tuple in the runtime library
GH-2194: Reimplement hilti::rt::currentExecutable without external dependency
GH-2201: HILTI_OPTIMIZER_PASSES has been removed
GH-2204: Minimum required GCC version bumped to gcc-12
GH-2222: Properly resolve and validate capture groups

Previously, incorrect uses of regular expression capture groups (e.g., $1, $2) were emitted to C++ without any analysis, causing compilation failures or unexpected behavior. Now, we validate capture groups and reject invalid Spicy code that was previously accepted.
GH-2245: Extend our notion of reserved C++ identifiers

When generating C++ code from Spicy sources, we transform Spicy identifiers which are not valid in C++. We extended the set of identifiers we transform, which might be visible when directly working with the generated C++ code, like e.g., in custom host applications.

GH-2144: Function parameter and local variable name clash leads to C++ error
GH-2154: Coercion from Null gets unhandled internal error
GH-2162: Fix ASAN false positive on ARM
GH-2175: Fix tuple assignment when coercing individual elements
GH-2177: Fix C++ code generation for struct parameters passed as references
GH-2184: FunctionParamVisitor fails to remove some redundant parameters
GH-2205: Uglify internal identifiers
Multiple fixes for issues reported by static analysis tools (clang-tidy, Coverity)
zeek/zeek#5008: Do not normalize ID names inside type information