Never mind, I found it.

Anyway, just one more question: if I want to use VS2017, should I put "<compatibility>vc141", or "<compatibility>vc14.1"?

This is what the file looks like right now (I changed the version from 1915 to 1916 and kept the last line from the default configuration file ("option.set keep-going : false ;"):

import option ;

using clang-win : : "C:\\Program Files\\LLVM\\bin\\clang-cl.exe" -fuse-ld=lld :

<compatibility>vc141

<compileflags>-fmsc-version=1916

<compileflags>-fms-compatibility

<compileflags>-fno-delayed-template-parsing

<compileflags>-flto=thin

<cxxflags>"/std:c++17"

<cxxflags>"/Zc:forScope"

<cxxflags>"/Zc:wchar_t"

<cxxflags>"/EHsc"

<cxxflags>"/Zc:inline"

<cxxflags>"/Gd"

<cxxflags>"/diagnostics:classic"

<cxxflags>-Wno-unknown-argument

<cxxflags>-Wno-unknown-pragmas

<cxxflags>-Wno-macro-redefined

<cxxflags>-Wno-unused-variable

<cxxflags>-Wno-mismatched-tags

<cxxflags>-Wno-deprecated-declarations

<cxxflags>-D_UNICODE

<cxxflags>-DUNICODE

<cxxflags>-DBOOST_USE_WINDOWS_H

<cxxflags>-DBOOST_NO_ANSI_APIS

<cxxflags>-DBOOST_USE_WINAPI_VERSION=0x1000

<cxxflags>-DBOOST_USE_WINDOWS_H=1

<cxxflags>-DNOMINMAX

<cxxflags>-DWIN32_LEAN_AND_MEAN

<cxxflags>-D_CRT_SECURE_NO_WARNINGS

;

option.set keep-going : false ;

I remember from a previous email thread that someone on this mailing list had given me a better configuration jamfile. I can't find it right now, so it'd be good if I could get that one again. It had a "using clang-win" line after the "import" command. And the <compatibility> tag, among some other things. I don't remember all of the commands, so I want to see it again.