jsoncpp 1.9.7 Release Work

Issues to fix before tagging 1.9.7, each in a separate CL.

Done

  • [x] #1656 — Fix uninitialized CMake variable JSONCPP_VERSION in version.in → Change @JSONCPP_VERSION@ to @jsoncpp_VERSION@

To Do

Security / Memory Safety

  • [ ] #1626 — MemorySanitizer: use-of-uninitialized-value in Json::Value::resolveReference → Uninitialized value detected by MSan in json_value.cpp. Need to identify and zero-initialize the offending member.

  • [ ] #1623 — Use-after-free: Json::Reader::parse stores raw pointers into input string → Reader stores begin_/end_ pointers that dangle after the input std::string goes out of scope. getFormattedErrorMessages() then reads freed memory. → Fix: copy the input document internally, or clearly document the lifetime requirement (the simpler option given the old Reader API is deprecated).

Correctness

  • [x] #1565 — Number parsing breaks when user sets a non-C locale (e.g. de_DE) → istringstream/ostringstream used for number parsing/writing inherit the global locale, which may use , as decimal separator instead of .. → Fix: imbue streams with std::locale::classic() in json_reader.cpp and json_writer.cpp.

  • [ ] #1546 — Control characters below 0x20 not rejected during parsing → JSON spec requires rejecting unescaped control characters. jsoncpp currently accepts them.

Build / CMake

  • [ ] #1634 — JSON_DLL_BUILD compile definition applied globally instead of per-target → add_compile_definitions scopes it to all targets; should use target_compile_definitions scoped to the shared lib only.

  • [x] #1598 — CMake 3.31 deprecation warning about compatibility with CMake < 3.10 → Update cmake_minimum_required to use <min>...<max> version range syntax, e.g. cmake_minimum_required(VERSION 3.10...3.31).

  • [x] #1595 — Linker errors with string_view API when jsoncpp built as C++11 but consumer uses C++17 → Root cause: JSONCPP_HAS_STRING_VIEW is not defined when building the library (forced C++11), but consumer with C++17 sees the string_view overloads in headers and tries to link them. → Fix options: (a) export JSONCPP_HAS_STRING_VIEW in the CMake config so consumers see the same value, or (b) drop CMAKE_CXX_STANDARD force and use target_compile_features(cxx_std_11) instead.

Skipped (not bugs)

  • #1548 — “Memory leak” after parsing large files: confirmed to be normal allocator behavior (OS doesn't immediately reclaim heap). Not a library bug.
  • #1533 — clear() then adding values fails: clear() preserves the value type by design. Confirmed user error.
  • #1547 — Trailing commas/garbage not rejected: existing behavior, controllable via strictMode(). Not a regression.