emscripten build is broken on MacOS and Linux

[iSuslov]

On MacOS I can't compile using emscripten no matter how hard I try.

Following the steps from #1543 using all the proposed suggestions it fails.
This collab (Linux) which worked before also fails: https://colab.research.google.com/drive/1Ah_WimDCdFKZSkwKBU3Q5SyHTVVdB6Tl?usp=sharing

Easiest way to reproduce in empty folder:

#!/bin/sh

# Setup

if [ ! -d emsdk ]; then
  git clone https://github.com/emscripten-core/emsdk.git
  cd emsdk
  ./emsdk install latest
  ./emsdk activate latest
  cd ..
fi

# Load emsdk env variables into this session
source ./emsdk/emsdk_env.sh

# use python bundled into emsdk
PYTHON_LOCATION="$(pwd)/emsdk/python"
PYTHON_VERSION=$(ls "$PYTHON_LOCATION")
PYTHON_PATH=$PYTHON_LOCATION/$PYTHON_VERSION/bin
export PATH="$PYTHON_PATH:$PATH"

# Link Python3 to Python:
alias python=python3 

if [ ! -d espeak-ng ]; then
  git clone https://github.com/espeak-ng/espeak-ng.git
fi
cd espeak-ng

# Building

./autogen.sh
./configure --prefix=/usr  --without-async --without-mbrola --without-sonic --without-pcaudiolib --without-klatt --without-speechplayer --with-extdict-cmn
make clean
make

cd src/ucd-tools
# PATCH 1: rename CHANGELOG.md to ChangeLog.md
mv CHANGELOG.md ChangeLog.md
./autogen.sh
emconfigure ./configure
emmake make clean
emmake make
cd ../..


make clean
emconfigure ./configure --prefix=/usr  --without-async --without-mbrola --without-sonic --without-pcaudiolib --without-klatt --without-speechplayer --with-extdict-cmn
# PATCH 2: 
sed -i '' 's/^using namespace std/\/\/&/' src/speechPlayer/src/speechWaveGenerator.cpp
emmake make clean
emmake make src/libespeak-ng.la

#failed

#cd emscripten
#emmake make clean
#emmake make

Error:

make: make src/libespeak-ng.la
  CC       src/ucd-tools/src/libespeak_ng_la-case.lo
  CC       src/ucd-tools/src/libespeak_ng_la-categories.lo
  CC       src/ucd-tools/src/libespeak_ng_la-ctype.lo
  CC       src/ucd-tools/src/libespeak_ng_la-proplist.lo
  CC       src/ucd-tools/src/libespeak_ng_la-scripts.lo
  CC       src/ucd-tools/src/libespeak_ng_la-tostring.lo
  CC       src/libespeak-ng/la-common.lo
  CC       src/libespeak-ng/la-compiledata.lo
  CC       src/libespeak-ng/la-compiledict.lo
  CC       src/libespeak-ng/la-dictionary.lo
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:180:11: error: conflicting types for 'ucd_isalnum'
  180 | int       iswalnum(wint_t);
      |           ^
src/include/compat/wctype.h:35:19: note: expanded from macro 'iswalnum'
   35 | #define iswalnum  ucd_isalnum
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:410:5: note: previous declaration is here
  410 | int ucd_isalnum(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:181:11: error: conflicting types for 'ucd_isalpha'
  181 | int       iswalpha(wint_t);
      |           ^
src/include/compat/wctype.h:36:19: note: expanded from macro 'iswalpha'
   36 | #define iswalpha  ucd_isalpha
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:417:5: note: previous declaration is here
  417 | int ucd_isalpha(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:182:11: error: conflicting types for 'ucd_isblank'
  182 | int       iswblank(wint_t);
      |           ^
src/include/compat/wctype.h:37:19: note: expanded from macro 'iswblank'
   37 | #define iswblank  ucd_isblank
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:424:5: note: previous declaration is here
  424 | int ucd_isblank(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:183:11: error: conflicting types for 'ucd_iscntrl'
  183 | int       iswcntrl(wint_t);
      |           ^
src/include/compat/wctype.h:38:19: note: expanded from macro 'iswcntrl'
   38 | #define iswcntrl  ucd_iscntrl
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:431:5: note: previous declaration is here
  431 | int ucd_iscntrl(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:185:11: error: conflicting types for 'ucd_isgraph'
  185 | int       iswgraph(wint_t);
      |           ^
src/include/compat/wctype.h:40:19: note: expanded from macro 'iswgraph'
   40 | #define iswgraph  ucd_isgraph
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:445:5: note: previous declaration is here
  445 | int ucd_isgraph(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:186:11: error: conflicting types for 'ucd_islower'
  186 | int       iswlower(wint_t);
      |           ^
src/include/compat/wctype.h:41:19: note: expanded from macro 'iswlower'
   41 | #define iswlower  ucd_islower
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:452:5: note: previous declaration is here
  452 | int ucd_islower(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:187:11: error: conflicting types for 'ucd_isprint'
  187 | int       iswprint(wint_t);
      |           ^
src/include/compat/wctype.h:42:19: note: expanded from macro 'iswprint'
   42 | #define iswprint  ucd_isprint
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:459:5: note: previous declaration is here
  459 | int ucd_isprint(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:188:11: error: conflicting types for 'ucd_ispunct'
  188 | int       iswpunct(wint_t);
      |           ^
src/include/compat/wctype.h:43:19: note: expanded from macro 'iswpunct'
   43 | #define iswpunct  ucd_ispunct
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:466:5: note: previous declaration is here
  466 | int ucd_ispunct(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:189:11: error: conflicting types for 'ucd_isspace'
  189 | int       iswspace(wint_t);
      |           ^
src/include/compat/wctype.h:44:19: note: expanded from macro 'iswspace'
   44 | #define iswspace  ucd_isspace
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:473:5: note: previous declaration is here
  473 | int ucd_isspace(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:190:11: error: conflicting types for 'ucd_isupper'
  190 | int       iswupper(wint_t);
      |           ^
src/include/compat/wctype.h:45:19: note: expanded from macro 'iswupper'
   45 | #define iswupper  ucd_isupper
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:480:5: note: previous declaration is here
  480 | int ucd_isupper(codepoint_t c);
      |     ^
In file included from src/libespeak-ng/dictionary.c:28:
In file included from src/include/compat/wchar.h:27:
/Users/user/Projects/espeak/emsdk/upstream/emscripten/cache/sysroot/include/wchar.h:191:11: error: conflicting types for 'ucd_isxdigit'
  191 | int       iswxdigit(wint_t);
      |           ^
src/include/compat/wctype.h:46:19: note: expanded from macro 'iswxdigit'
   46 | #define iswxdigit ucd_isxdigit
      |                   ^
./src/ucd-tools/src/include/ucd/ucd.h:487:5: note: previous declaration is here
  487 | int ucd_isxdigit(codepoint_t c);
      |     ^
11 errors generated.
make: *** [src/libespeak-ng/la-dictionary.lo] Error 1
emmake: error: 'make src/libespeak-ng.la' failed (returned 2)