--text follows this line--
Editing a C header file and trying to add a doxygen-style comment.  Itried to enter an open parenthesis in the comment and emacs hangs.  Iwas able to replicate this multiple times.  I was able to narrow it downto these lines being present in the file:
/* make sure LogStorageTable_t is packed */COMPILE_TIME_ASSERT(sizeof(LogStorageTable_t) == ((sizeof(LogStorageArea_t) *                                                   LOG_STORAGE_NUM) +                                                  sizeof(uint16_t)));
/** hang if open parenthesis is pressed here -> 
Entering a open parenthesis in the above line causes emacs to hang.  Isent signal USR2 to the process and got the attached screen shot (sorry,couldn't cut and paste from the emacs window after the hang).


In GNU Emacs 26.1 (build 1, x86_64-unknown-cygwin, GTK+ Version 3.22.28) of 2018-05-28 built on DESKTOPRepository revision: d802fa4a0642157d7aff9a9d599785df7604e4d1Windowing system distributor 'The Cygwin/X Project', version 11.0.12000000Recent messages:Fill column set to 79 (was 70)For information about GNU Emacs and the GNU system, type <f1> C-a.Making completion list... [2 times]
Configured using: 'configure --srcdir=/home/kbrown/src/cygemacs/emacs-26.1-1.x86_64/src/emacs-26.1 --prefix=/usr --exec-prefix=/usr --localstatedir=/var --sysconfdir=/etc --docdir=/usr/share/doc/emacs --htmldir=/usr/share/doc/emacs/html -C 'CFLAGS=-ggdb -O2 -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -fstack-protector-strong --param=ssp-buffer-size=4 -fdebug-prefix-map=/home/kbrown/src/cygemacs/emacs-26.1-1.x86_64/build=/usr/src/debug/emacs-26.1-1 -fdebug-prefix-map=/home/kbrown/src/cygemacs/emacs-26.1-1.x86_64/src/emacs-26.1=/usr/src/debug/emacs-26.1-1' CPPFLAGS= LDFLAGS='
Configured features:XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND DBUS GSETTINGS NOTIFY ACLGNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB TOOLKIT_SCROLL_BARSGTK3 X11 THREADS LCMS2
Important settings:  value of $LANG: en_US.UTF-8  locale-coding-system: utf-8-unix
Major mode: Lisp Interaction
Minor modes in effect:  tooltip-mode: t  global-eldoc-mode: t  eldoc-mode: t  electric-indent-mode: t  mouse-wheel-mode: t  tool-bar-mode: t  menu-bar-mode: t  file-name-shadow-mode: t  global-font-lock-mode: t  font-lock-mode: t  blink-cursor-mode: t  auto-composition-mode: t  auto-encryption-mode: t  auto-compression-mode: t  line-number-mode: t  transient-mark-mode: t
Load-path shadows:None found.
Features:(shadow sort mail-extr emacsbug message rmc puny seq byte-opt gvbytecomp byte-compile cconv cl-loaddefs cl-lib dired dired-loaddefsformat-spec rfc822 mml easymenu mml-sec password-cache epa derived epgepg-config gnus-util rmail rmail-loaddefs mm-decode mm-bodies mm-encodemail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047rfc2045 ietf-drums mm-util mail-prsvr mail-utils elec-pair time-datemule-util tooltip eldoc electric uniquify ediff-hook vc-hookslisp-float-type mwheel term/x-win x-win term/common-win x-dnd tool-bardnd fontset image regexp-opt fringe tabulated-list replace newcommenttext-mode elisp-mode lisp-mode prog-mode register page menu-barrfn-eshadow isearch timer select scroll-bar mouse jit-lock font-locksyntax facemenu font-core term/tty-colors frame cl-generic cham georgianutf-8-lang misc-lang vietnamese tibetan thai tai-viet lao koreanjapanese eucjp-ms cp51932 hebrew greek romanian slovak czech europeanethiopic indian cyrillic chinese composite charscript charpropcase-table epa-hook jka-cmpr-hook help simple abbrev obarray minibuffercl-preloaded nadvice loaddefs button faces cus-face macroexp filestext-properties overlay sha1 md5 base64 format env code-pages mulecustom widget hashtable-print-readable backquote dbusbind gfilenotifylcms2 dynamic-setting system-font-setting font-render-settingmove-toolbar gtk x-toolkit x multi-tty make-network-process emacs)
Memory information:((conses 16 95955 10383) (symbols 48 20382 1) (miscs 40 39 143) (strings 32 28537 1006) (string-bytes 1 747190) (vectors 16 14589) (vector-slots 8 495926 9216) (floats 8 50 87) (intervals 56 248 0) (buffers 992 12))