[glibmm/glibmm-master-use-dllexport] glibmm: Update glibmmconfig.h.[in|meson] for MSVC

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

commit 1f006eef387a519abfff9392dd158332fbac390d
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Mon Mar 9 11:58:33 2020 +0800

    glibmm: Update glibmmconfig.h.[in|meson] for MSVC
    
    Visual Studio 2015 or later has thread_local, so make sure that it is
    enabled.
    
    Also update for Visual Studio 2017+ as the compiler does allow static
    members to be initialized inline to std::string::npos
    (GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS), but use a work
    around for pre-Visual Studio 2015 so that we do not get a linker error
    as GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS is not supported.

 glib/glibmm/ustring.h     |  5 +++++
 glib/glibmmconfig.h.in    | 11 +++++++++++
 glib/glibmmconfig.h.meson | 11 +++++++++++
 3 files changed, 27 insertions(+)
---
diff --git a/glib/glibmm/ustring.h b/glib/glibmm/ustring.h
index c9e24cd1..f0be919f 100644
--- a/glib/glibmm/ustring.h
+++ b/glib/glibmm/ustring.h
@@ -29,6 +29,11 @@
 #include <string>
 #include <type_traits>
 
+/* work around linker error on Visual Studio if we don't have GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS */
+#if (_MSC_VER >= 1600) && !defined (GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS)
+const std::basic_string<char>::size_type std::basic_string<char>::npos = 
(std::basic_string<char>::size_type) -1;
+#endif
+
 namespace Glib
 {
 
diff --git a/glib/glibmmconfig.h.in b/glib/glibmmconfig.h.in
index aa158038..7cf76292 100644
--- a/glib/glibmmconfig.h.in
+++ b/glib/glibmmconfig.h.in
@@ -98,7 +98,18 @@
 #define thread_local __declspec (thread)
 #endif
 
+#else
+
+/* thread_local is supported on Visual Studio 2015+ */
+#define GLIBMM_CAN_USE_THREAD_LOCAL 1
+
 #endif /* _MSC_VER < 1900 */
+
+/* We have GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS for Visual Studio 2017+ */
+#if (_MSC_VER >= 1910)
+#define GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS 1
+#endif
+
 #endif /* GLIBMM_MSC */
 
 /* Enable DLL-specific stuff only when not building a static library */
diff --git a/glib/glibmmconfig.h.meson b/glib/glibmmconfig.h.meson
index 801e3995..55aa3bac 100644
--- a/glib/glibmmconfig.h.meson
+++ b/glib/glibmmconfig.h.meson
@@ -100,7 +100,18 @@
 #define thread_local __declspec (thread)
 #endif
 
+#else
+
+/* thread_local is supported on Visual Studio 2015+ */
+#define GLIBMM_CAN_USE_THREAD_LOCAL 1
+
 #endif /* _MSC_VER < 1900 */
+
+/* We have GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS for Visual Studio 2017+ */
+#if (_MSC_VER >= 1910)
+#define GLIBMM_HAVE_ALLOWS_STATIC_INLINE_NPOS 1
+#endif
+
 #endif /* GLIBMM_MSC */
 
 /* Enable DLL-specific stuff only when not building a static library */