plusplus: Fix dependency file creation (multiple target patterns)

[winspool]

Without the fix, OpenWatcom creates broken dependency files.
(everything is in one line)

GNU Make can build the c++ autotools project once (target files are missing),
but any following make to update the targets fails with a message similar to:

*** multiple target patterns. Stop

An example autotools project is attached:

./bootstrap
CC=owcc  CXX=owcc  CFLAGS="-v"  CXXFLAGS="-v"  ./configure
# first make works:
make

# a touch is optional:
# touch foo2.cpp
 
# a following make fails:
make

tst_foo.tar.gz

--
Regards Detlef

[jmalak]

Thanks for your contribution

[iainnicol]

Hi @winspool Detlef. Currently Open Watcom uses a weird software license. We want to relicense Open Watcom under “Apache 2.0 license plus LLVM Exceptions”. Is this okay with you? Please see the wiki for more information.

[winspool]

We want to relicense Open Watcom under “Apache 2.0 license plus LLVM Exceptions”. Is this okay with you?

Yes, sure