ldc-developers/ldc v1.22.0-beta1

LDC 1.22.0-beta1

on GitHub

Big news

• Frontend, druntime and Phobos are at version 2.092.0+. (#3413, #3416, #3429, #3434)
• AArch64: All known ABI issues have been fixed. C(++) interop should now be on par with x86_64, and variadics usable with core.{vararg,stdc.stdarg}. (#3421)
• Windows hosts: DMD's Visual C++ toolchain detection has been adopted. As that's orders of magnitude faster than the previous method involving the MS batch file, auto-detection has been enabled by default, so if you have a non-ancient Visual C++ installation, it will now be used automatically for linking. The environment setup has been reduced to the bare minimum (LIB and PATH). (#3415)
• Link-time overridable @weak functions are now emulated for Windows targets and work properly for ELF platforms. For ELF, LDC doesn't emit any COMDATs anymore. (#3424)
• New ldc.gccbuiltins_{amdgcn,nvvm} for AMD GCN and NVIDIA PTX targets. (#3411)

Platform support

• Supports LLVM 3.9 - 10.0.

Bug fixes

• Casting (static and dynamic) arrays to vectors now loads the data instead of splatting the first element. (#3418, #3419)
• Fix return statements potentially accessing memory from destructed temporaries. (#3426)
• Add proper support for -checkaction=halt. (#3430, #3431)

Internals

• When printing compile-time reals to hex strings (mangling, .di headers), LDC now uses LLVM instead of the host C runtime, for proper and consistent results. (#3410)
• One limitation for exotic hosts wrt. C long double precision has been lifted. (#3414)
• For AVR targets, the compiler now predefines AVR and emits all TLS globals as regular __gshared ones. (#3420)

Known issues

• When building LDC, old LDC 0.17.*/ltsmaster host compilers miscompile LDC ≥ 1.21, leading to potential segfaults of the built LDC. Ltsmaster can still be used to bootstrap a first compiler and then let that compiler compile itself. (#3354)
• Buggy older ld.bfd linker versions may wrongly strip out required symbols, e.g., ModuleInfos (so that e.g. no module ctors/dtors are run). LDC defaults to ld.gold on Linux.
• LDC does not zero the padding area of a real variable. This may lead to wrong results if the padding area is also considered. See #770. Does not apply to real members inside structs etc.