[pangomm/master.msvc.improvements] NMake Makefiles: Support Meson-built libsigc++

[Chun-wei Fan <fanchunwei src gnome org>]

commit a6016f0795dcb8a142c7790566c77df1235d42ef
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Fri Feb 21 17:27:13 2020 +0800

    NMake Makefiles: Support Meson-built libsigc++
    
    Add an option USE_MESON_LIBS for the NMake Makefile command line which
    allows one to easily link to Meson-built libsigc++, as the .lib
    filenames are different for libsigc++ built with NMake and Meson.
    
    Note that when cairomm and glibmm gains Meson build support, one must
    choose between Meson-built and NMake-built flavors for these as
    well-mixing between flavors will not be supported, and Meson build files
    will prefer Meson-built flavors of these as well.

 MSVC_NMake/config-msvc.mak | 7 ++++++-
 README.win32               | 4 +++-
 2 files changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/MSVC_NMake/config-msvc.mak b/MSVC_NMake/config-msvc.mak
index d331f76..07f10b5 100644
--- a/MSVC_NMake/config-msvc.mak
+++ b/MSVC_NMake/config-msvc.mak
@@ -46,9 +46,14 @@ LIBPANGOMM_CFLAGS = /DPANGOMM_BUILD $(PANGOMM_BASE_CFLAGS) $(PANGOMM_EXTRA_INCLU
 # We build pangomm-vc$(VSVER)0-$(PANGOMM_MAJOR_VERSION)_$(PANGOMM_MINOR_VERSION).dll or
 #          pangomm-vc$(VSVER)0-d-$(PANGOMM_MAJOR_VERSION)_$(PANGOMM_MINOR_VERSION).dll at least
 
+!ifdef USE_MESON_LIBS
+LIBSIGC_LIBNAME = sigc-$(LIBSIGC_MAJOR_VERSION).$(LIBSIGC_MINOR_VERSION)
+LIBSIGC_DLL = $(LIBSIGC_LIBNAME)-0.dll
+!else
 LIBSIGC_LIBNAME = sigc-vc$(VSVER)0$(DEBUG_SUFFIX)-$(LIBSIGC_MAJOR_VERSION)_$(LIBSIGC_MINOR_VERSION)
-
 LIBSIGC_DLL = $(LIBSIGC_LIBNAME).dll
+!endif
+
 LIBSIGC_LIB = $(LIBSIGC_LIBNAME).lib
 
 GLIBMM_LIBNAME = glibmm-vc$(VSVER)0$(DEBUG_SUFFIX)-$(GLIBMM_MAJOR_VERSION)_$(GLIBMM_MINOR_VERSION)
diff --git a/README.win32 b/README.win32
index f2203bd..2c8a90e 100644
--- a/README.win32
+++ b/README.win32
@@ -52,7 +52,9 @@ all the depedent libraries could be found in $(PREFIX), which is at
 $(srcroot)\..\vs15\$(Platform) by default.  Run
 'nmake /f Makefile.vc CFG=[release|debug]' to build pangomm.  If a
 different $(PREFIX) is desired rather than the aforementioned default,
-pass in PREFIX=$(PATH) into your command line.
+pass in PREFIX=$(PATH) into your command line.  If you wish to use
+a Meson-built libsigc++ and Meson-built -mm dependencies for your build,
+pass in USE_MESON_LIBS=1 into your NMake command line.
 
 A 'clean' target is supported to remove all the built object files and
 intermediate files that are generated during the build, while an