Build with MinGW

[Bastian M. <bma...@we...>]

When trying to build with MinGW and cairo/pango, I noticed a weird 
problem: make seems to have problems with variables defined like this:

	CAIRO_CFLAGS = $(shell pkg-config --cflags cairo)

Make `echo`s those variables just fine, but the actual build command 
gets mixed up. Here's an example (TERMFLAGS includes CAIRO_FLAGS):
The rule

term.$(O): term.c term.h plot.h setshow.h bitmap.h $(CORETERM)
	echo $(TERMFLAGS)
	echo
	$(CC) -c $(CFLAGS) $(TERMFLAGS) $(S)/term.c

yields:

-DGNUPLOT_PS_DIR="share/PostScript" -DGNUPLOT_JS_DIR="share/js"
<snip>
libs/include/freetype2 -Id:/Software/mingw-libs/include/libpng14
<snip>

gcc -c  -g -I. -I../../src -D_Windows -DHAVE_CONFIG_H -DPIPES <snip>
-Id:/Software/mingw-libs/include -Id:/Software/mingw-libs/include/freety
  ../../src/term.c/mingw-libs/include/libpng14
: Invalid argument
make: *** [term.o] Error 1

Note that the source file string "../../src/term.c" overlays part of the 
TERMFLAGS string.

Instead, I have put the result of `pkg-config --cflags cairo` directly 
in the definition of CAIRO_CFLAGS and it works as expected.

I have no idea what's going on here. Has anybody else seen that 
behaviour, or an explanation?

   Bastian