0.1.1

Released on 2026-09-29.

Serc 0.1.1 adds Python optimization modes and hash-based bytecode caches,
improves compilation performance, and expands compatibility with CPython.

Enhancements

• Compile with Python’s -O and -OO optimization modes through CLI flags or
  CompileOptions (#841;
  #841)
• Generate checked or unchecked hash-based bytecode caches with
  --invalidation-mode or CompiledModule::to_hash_pyc (#840;
  #840)
• Opt into caller-selected decimal literal parsing limits through new text,
  byte, and path compilation APIs (#911;
  #911)
• Model the caller’s integer-to-string limit when formatting duplicate
  mapping-key diagnostics through opt-in compilation APIs (#887;
  #887)
• Reproduce floating-point constant folding from documented CPython 3.14.5 GCC
  and Clang builds on supported GNU/Linux x86-64 hosts by selecting a native
  build profile (#824; #824)

Bug fixes

• Produce CPython-compatible control flow, source locations, exception tables,
  and constant sharing under -O and -OO (#912;
  #912)
• Preserve requested .opt-N.pyc cache suffixes for repeated optimization flags
  while applying -OO semantics (#912;
  #912)
• Compile nested continue statements in finally suites without negative
  stack-depth errors or incorrect exception restoration (#825;
  #825)
• Compile deeply nested expressions and postponed annotations without
  overflowing the compiler stack (#827;
  #827)
• Honor selected native build profiles throughout nested constant folding
  (#827; #827)
• Keep enclosing cleanup and exception handlers active when tracing raises at a
  nested no-op finally suite (#900;
  #900) (#908;
  #908)
• Convert StopIteration raised by tracing in nested generator finalizers into
  RuntimeError instead of silently terminating the generator
  (#903; #903)
• Resolve private type-parameter names and their mangled aliases to the same
  binding in generic class headers (#828;
  #828)
• Preserve marshal object identity for retained native startup names on Python
  3.14 (#830; #830)
• Remove redundant NOP instructions before module annotations after literal
  and negated conditions on Python 3.14 and 3.15 (#894;
  #894) (#906;
  #906)
• Match CPython opcode ordering when breaking from an exceptional finally
  suite into nested handler cleanup (#829;
  #829)
• Preserve async-comprehension assertion exits in terminal conditionals on
  Python 3.12 (#889; #889)
• Match CPython’s exception-table coverage for markers in nested finalizers
  after a handler returns (#904;
  #904)
• Match CPython bytecode and exception-table ownership after branching try
  bodies enter nested finalizers (#909;
  #909)
• Match CPython 3.12 source locations for successful assertions at the end of
  finally suites (#907;
  #907)
• Reject lambdas and comprehensions in Python 3.12 generic headers when their
  annotation scopes can see an enclosing class namespace (#831;
  #831)
• Reject repeated explicit keyword arguments in calls, including unreachable
  code (#845; #845)
• Reject invalid uses of __debug__ in attributes, call and class keywords, and
  class patterns according to the target Python version (#847;
  #847)
• Reject commas immediately following bare yield expressions while continuing
  to accept parenthesized yields and yield tuples (#846;
  #846)
• Reject Python sources with more than 99 active indentation levels
  (#834; #834)
• Enforce CPython’s default 4,300-digit limit for decimal integer literals
  (#835; #835)
• Reject parameter specification and variadic type-parameter defaults when
  targeting Python 3.12 (#869;
  #869) (#870;
  #870)
• Include the repeated type-parameter name in duplicate-name diagnostics
  (#850; #850)
• Match CPython diagnostics for unknown __future__ features
  (#858; #858)
• Match CPython diagnostics for misplaced __future__ imports
  (#860; #860)
• Prioritize misplaced __future__ imports over unknown features in the same
  statement (#865; #865)
• Match CPython diagnostics and source ranges for duplicate mapping-pattern keys
  (#857; #857)
• Reject large integer mapping-pattern keys that compare equal to floating-point
  or complex keys (#861;
  #861)
• Preserve lone surrogates when validating and folding mapping-pattern keys
  (#877; #877)
• Match CPython diagnostics for assignment expressions targeting attributes
  (#871; #871)
• Match CPython diagnostics for unparenthesized tuples after yield from
  (#872; #872)
• Preserve type-alias default diagnostics when later syntax errors are also
  present (#867; #867)
• Report the appropriate comprehension-specific error for yield and
  yield from expressions inside comprehensions (#879;
  #879)
• Report direct dictionary-comprehension value yield errors before
  corresponding key errors (#880;
  #880)
• Report nested comprehension yield errors in operand order
  (#884; #884)
• Prioritize comprehension yield errors over earlier bare starred expressions
  (#885; #885)
• Prioritize supported comprehension yield errors over async-generator
  value-return errors (#895;
  #895)
• Match CPython diagnostics for await inside synchronous functions and lambdas
  (#896; #896)
• Resolve invalid global and nonlocal declarations before reporting
  mapping-pattern errors (#881;
  #881)

Performance

• Reduce compilation overhead across scope analysis, source handling, assembler
  passes, and marshal serialization (#848;
  #848)