March 05, 2019
https://issues.dlang.org/show_bug.cgi?id=19718

          Issue ID: 19718
           Summary: DMD 2.085 changes to gsroa make DCD crashing
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: b2.temp@gmx.com

shell script to reproduce the issue and verify that it's fixed:

---
killall dcd-server

if [[ ! -d dcd ]]; then
    git clone https://github.com/dlang-community/dcd.git
    git submodule update --init
fi

cd dcd

if [[ ! -f bin/dcd-server ]]; then
    make
fi

pos=`grep -boa "ASTVisitor" libdparse/src/dparse/ast.d | head -1`
pos=`echo $pos | grep -o [0-9]*`
let pos++

bin/dcd-server &
sleep 2
res=`bin/dcd-client --doc -c$pos libdparse/src/dparse/ast.d`

if [[ ${res} == "Implements the \$(LINK2
http://en.wikipedia.org/wiki/Visitor_pattern, Visitor Pattern)\nfor the various
AST classes" ]]; then
    echo "FIXED !!"
fi
---

Note that you'll certainly have to tweak the makefile of DCD in order to use
the devel version of DMD, line 9 (DMD := <your devel dmd here...>)
Manual digging in the stable branch shows that the regression come from this
DMD PR: https://github.com/dlang/dmd/pull/9281

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