Bug 7810 – [CTFE] Typesafe variadic function with array of structs

Using dmd 2.059 trunk import std.regex; //enum re = ctRegex!`(^[a-z]+)|([A-Z0-9][a-z0-9]+)|([A-Z]+)|([a-z]+)`; //enum re = ctRegex!`(a)|(b)`; enum re = ctRegex!`a|b`; void main() {} /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(1150): Error: assert(this.ir[cast(ulong)orStart].code() == cast(IR)129u) failed /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(876): called from here: this.parseRegex() /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6428): called from here: parser.this(pattern,flags) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6412): called from here: regexImpl(pattern,flags) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6437): called from here: regex("a|b",[]) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(1150): Error: assert(this.ir[cast(ulong)orStart].code() == cast(IR)129u) failed /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(876): called from here: this.parseRegex() /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6428): called from here: parser.this(pattern,flags) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6412): called from here: regexImpl(pattern,flags) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6439): called from here: regex("a|b",[]) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6439): called from here: ctGenRegExCode(regex("a|b",[])) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(1150): Error: assert(this.ir[cast(ulong)orStart].code() == cast(IR)129u) failed /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(876): called from here: this.parseRegex() /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6428): called from here: parser.this(pattern,flags) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6412): called from here: regexImpl(pattern,flags) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6446): called from here: regex("a|b",[]) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6446): called from here: StaticRegex(null,Regex(null,null,null,0u,0u,0u,0u,0u,null,null,ShiftOr(null,0u,0u))).this(regex("a|b",[]),& func) /home/simendsjo/code/dmd-trunk/build/src/phobos/std/regex.d(6463): Error: template instance std.regex.ctRegexImpl!("a|b",[]) error instantiating re.d(4): instantiated from here: ctRegex!("a|b") re.d(4): Error: template instance std.regex.ctRegex!("a|b") error instantiating

Created attachment 1094 Stripped down regex parser

It's a bug in CTFE not in Phobos. R-T version runs the same code and doesn't hit the assert. See reduced test case.

*** Issue 7567 has been marked as a duplicate of this issue. ***

Doesn't appear to require ctRegex to trigger. This produces the same assertion failure. import std.regex; auto r = regex(r"(a|c"); void main() { } This worked in 2.058 but not 2.059.

(In reply to comment #4) > Doesn't appear to require ctRegex to trigger. This produces the same assertion > failure. > > import std.regex; > > auto r = regex(r"(a|c"); > > void main() { } > > This worked in 2.058 but not 2.059. not the same. And yes, global variable == CTFE parser. + r"(a|c" unbalanced paren, so it should eventually throw exception but it asserts before it have the chance to do that.

I've finally pinned down this bugger. The problem is in typesafe variadic function if the parameter type is a struct. See simple test below: //encoded IR instruction struct Bytecode { uint raw; } int fn1(T)(T[] items...) { assert(items[0] == 20); return 42; } int fn2(T)(T[] items...) { assert(items[0] == Bytecode(20)); return 42; } //this passes... static assert(fn1(20, 30) == 42); //this dies inside of fn2 static assert(fn2(Bytecode(20), Bytecode(30)) == 42); void main() {//both of these pass at R-T assert(fn1(20, 30) == 42); assert(fn2(Bytecode(20), Bytecode(30)) == 42); } Output: sr_micro.d(15): Error: assert(items[0u] == Bytecode(20u)) failed sr_micro.d(23): called from here: fn2((Bytecode[2u] __arrayArg6 = void; , __arrayArg6[0u] = Bytecode(20u) , __arrayArg6[1u] = Bytecode(30u) , cast(Bytecode[])__arrayArg6)) sr_micro.d(23): while evaluating: static assert(fn2((Bytecode[2u] __arrayArg6 = void; , __arrayArg6[0u] = Bytecode(20u) , __arrayArg6[1u] = Bytecode(30u) , cast(Bytecode[])__arrayArg6)) == 42)

Problem happens when an array is initialized to void in global scope (outside of CTFE) and then modified in CTFE. Haven't fixed this yet.

(In reply to comment #7) > Problem happens when an array is initialized to void in global scope (outside > of CTFE) and then modified in CTFE. Haven't fixed this yet. Thanks for looking into it. It took soo long to reduce but at least now I have an idea of a workaround.

Further reduced shows it's a problem with void initialized static arrays. I have a fix. int bug7810() { int[1][3] x = void; x[0] = [2]; x[1] = [7]; assert(x[0][0] == 2); return 1; } static assert(bug7810());

Commits pushed to master at https://github.com/D-Programming-Language/dmd https://github.com/D-Programming-Language/dmd/commit/7d133964da2a5c0c794b82d42f3f3c9cbfdcf078 Fix issue 7810 [CTFE] Typesafe variadic function with array of structs It's actually a problem with void-initialized static arrays. This was the root cause of a compile-time regexp bug. https://github.com/D-Programming-Language/dmd/commit/eaa03fefeb1a698f586d5f5a09068f3433bf4b29 Merge pull request #1155 from donc/ctfe7810array_voidinit Fix issue 7810 [CTFE] Typesafe variadic function with array of structs

Fixed for D2

Fixed for D1.

*** Issue 8725 has been marked as a duplicate of this issue. ***

*** Issue 8805 has been marked as a duplicate of this issue. ***