Add wsl config as an environment to otp build tools

Allows "cross" building with native windows from WSL linux.

Currently we only support building on the windows disk,
old WSL installations can not access WSL disk at all and
on the newer ones it is still problematic.

Thus, create the erlang src/git on /mnt/c/<dir>/otp/
and don't create links from wsl to windows, that will
cause problems for the scripts and will not work.
Use:
  cd /mnt/c/<dir>/otp
  eval `./otp_build env_win32 ARCH`
  ./otp_build

To build with emu_cc (32 and 64) it needs mingw-gcc
On wsl ubuntu use: 'sudo apt-get install gcc-mingw-w64'
to install everything for both build targets.

Additional commit comments:
- Let configure (crypto/wx) search in '/mnt/c/DocumentedPaths'

- Use -Z7 for debug info
   Add debug info into .o files instead of vc120.pdb which
   makes parallel compilation more stable.

- Use mingw-gcc as emu_cc
   Packages available in ubuntu.

- Use $ERL_TOP/tmp for temporary directories
   Linux /tmp is not accessable in older wsl (arrived in Win 10 19.03).

- Quoting is problematic
   It seems to be impossible to handle 'spaces' in paths correct,
   the autotools are just not prepared to handle that
   and we depend on them.

Currently NOT supported but have been prepared for:
-Using wsl as disk
-- Ensure directory exists
    If linux file server is overloaded it may take a while until the
    directory is visible for windows programs.
-- Use absolute paths
    Windows tools needs absolute (the network path) to access
    files on the wsl drive.
    Also we can not use mixed mode (forward slashes) for network paths,
    windows programs don't recognize //wsl$/<install>/

1 files changed, 19 insertions, 0 deletions

diff --git a/erts/etc/win32/wsl_tools/reg_query.sh b/erts/etc/win32/wsl_tools/reg_query.sh
new file mode 100755
index 0000000000..c05f00dfa1
--- /dev/null
+++ b/erts/etc/win32/wsl_tools/reg_query.sh
@@ -0,0 +1,19 @@
+#! /bin/sh
+
+mkdir -p $ERL_TOP/tmp
+BAT_FILE=$ERL_TOP/tmp/w$$.bat
+if [ -z "$1" -o -z "$2" ]; then
+    echo "Usage:" "$0" '<key> <valuename>'
+    exit 1
+fi
+BACKED=`echo "$1" | sed 's,/,\\\\,g'`
+
+if [ $CONFIG_SUBTYPE = "win64" ]; then
+    REG_OPT=" /reg:64"
+else
+    REG_OPT=" /reg:32"
+fi
+
+WIN_BAT_FILE=`w32_path.sh -w $BAT_FILE`
+RESULT=`reg.exe query "$BACKED" /v "$2" $REG_OPT | sed 's@\\\@/@g' | tr -d '\r\n'`
+echo "$RESULT" | sed "s,.*REG_[^ ]* *,,g"