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| + | == D language for programming competitions == | ||
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| + | Not everything is perfect: | ||
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| + | * Hash tables are vulnerable: https://issues.dlang.org/show_bug.cgi?id=7179 and https://codeforces.com/contest/1676/submission/156707849 | ||
| + | * Arithmetic overflows detection is not the best | ||
| + | * 128-bit data type is missing | ||
| + | * [https://github.com/dlang/phobos/blob/master/std/bigint.d std.bigint] is slow (not using GMP as a backend) | ||
| + | * [https://github.com/dlang/phobos/blob/master/std/random.d std.random] is slow: https://codeforces.com/blog/entry/99292#comment-881097 | ||
| + | |||
== GDC tips and tricks == | == GDC tips and tricks == | ||
Revision as of 23:11, 10 May 2022
Contents
D language for programming competitions
Not everything is perfect:
- Hash tables are vulnerable: https://issues.dlang.org/show_bug.cgi?id=7179 and https://codeforces.com/contest/1676/submission/156707849
- Arithmetic overflows detection is not the best
- 128-bit data type is missing
- std.bigint is slow (not using GMP as a backend)
- std.random is slow: https://codeforces.com/blog/entry/99292#comment-881097
GDC tips and tricks
GDC 11+ requires "-flto" or "-fno-weak-templates" option to avoid a major performance regression: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102765
Shared library linking workaround to run phobos unit tests: https://bugzilla.gdcproject.org/show_bug.cgi?id=199
Demangle symbols: https://dlang.org/phobos/std_demangle.html
Mingw build and test instructions: TODO
Arithmetic overflows
TODO: create a new DIP? https://forum.dlang.org/post/rclilxjpnjvexggncfhd@forum.dlang.org
TODO: Atomic operations and arithmetic overflows?
TODO: Unsigned overflows?
GDC supports "-ftrapv" easter egg option for trapping signed overflows.
Relevant links:
- https://dlang.org/phobos/core_checkedint.html
- https://forum.dlang.org/post/s3dm64$2f2i$1@digitalmars.com
- https://news.ycombinator.com/item?id=24575780
- https://gcc.gnu.org/legacy-ml/gcc/2014-07/msg00251.html
- https://gcc.gnu.org/onlinedocs/gccint/Integer-library-routines.html
GCC history of -fno-strict-aliasing and -fwrapv:
- https://www.mail-archive.com/redhat-list@redhat.com/msg18009.html
- https://lists.gnu.org/archive/html/autoconf-patches/2006-12/msg00091.html
- https://lists.gnu.org/archive/html/bug-gnulib/2006-12/msg00094.html
- https://gcc.gnu.org/legacy-ml/gcc/2008-02/msg00732.html
Associative arrays and hash collisions
https://forum.dlang.org/post/navsnrjweslsqeaawsev@forum.dlang.org
Relevant links:
