From 99aa50aff83c1f03a532fb0053fa5dd7c7d5c20e Mon Sep 17 00:00:00 2001
From: Luigi Ballabio <luigi.ballabio@gmail.com>
Date: Tue, 23 Jul 2024 12:45:11 +0200
Subject: [PATCH] Remove support for Visual C++ 2015.

This makes it possible to start using features from the C++17 standard.
---
 .appveyor.yml      | 21 ++++-----------------
 .ci/VS2015.props   | 18 ------------------
 ql/config.msvc.hpp |  4 ++--
 ql/errors.cpp      |  2 +-
 ql/handle.hpp      |  4 ----
 5 files changed, 7 insertions(+), 42 deletions(-)
 delete mode 100644 .ci/VS2015.props

diff --git a/.appveyor.yml b/.appveyor.yml
index d201a8c07be..3105f112bca 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -1,27 +1,14 @@
-image:
-  - Visual Studio 2015
-  - Visual Studio 2017
+image: Visual Studio 2017
 
 platform: x64
 configuration: Release
 
 version: ci.{build}
 
+before_build:
+  - COPY .ci\VS2017.props .\Build.props
+
 build:
   parallel: false
   project: QuantLib.sln
   verbosity: normal
-
-for:
--
-  matrix:
-    only:
-      - image: Visual Studio 2015
-  before_build:
-    - COPY .ci\VS2015.props .\Build.props
--
-  matrix:
-    only:
-      - image: Visual Studio 2017
-  before_build:
-    - COPY .ci\VS2017.props .\Build.props
diff --git a/.ci/VS2015.props b/.ci/VS2015.props
deleted file mode 100644
index cbac65b4406..00000000000
--- a/.ci/VS2015.props
+++ /dev/null
@@ -1,18 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <ImportGroup Label="PropertySheets" />
-  <PropertyGroup Label="UserMacros" />
-  <PropertyGroup>
-    <LinkIncremental>false</LinkIncremental>
-  </PropertyGroup>
-  <ItemDefinitionGroup>
-    <ClCompile>
-      <AdditionalIncludeDirectories>C:\Libraries\boost_1_69_0;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <Optimization>Disabled</Optimization>
-    </ClCompile>
-    <Link>
-      <AdditionalLibraryDirectories>C:\Libraries\boost_1_69_0\lib64-msvc-14.0;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
-    </Link>
-  </ItemDefinitionGroup>
-  <ItemGroup />
-</Project>
diff --git a/ql/config.msvc.hpp b/ql/config.msvc.hpp
index ef0e22da753..ffd80a294df 100644
--- a/ql/config.msvc.hpp
+++ b/ql/config.msvc.hpp
@@ -25,8 +25,8 @@
 #include <ql/userconfig.hpp>
 
 // first things first
-#if (_MSC_VER < 1900)
-#  error "versions of Visual C++ prior to VC++ 2015 are no longer supported"
+#if (_MSC_VER < 1910)
+#  error "versions of Visual C++ prior to VC++ 2017 are no longer supported"
 #endif
 
 /*******************************************
diff --git a/ql/errors.cpp b/ql/errors.cpp
index aa6b0081b49..1a6c57b37c9 100644
--- a/ql/errors.cpp
+++ b/ql/errors.cpp
@@ -22,7 +22,7 @@
 
 namespace {
 
-    #if defined(_MSC_VER) || defined(__BORLANDC__)
+    #if defined(_MSC_VER)
     // allow Visual Studio integration
     std::string format(
                        #ifdef QL_ERROR_LINES
diff --git a/ql/handle.hpp b/ql/handle.hpp
index 6ba37134446..04a0e27fe8c 100644
--- a/ql/handle.hpp
+++ b/ql/handle.hpp
@@ -127,11 +127,7 @@ namespace QuantLib {
         /*! \deprecated Use one of the constructors taking shared_ptr.
                         Deprecated in version 1.35.
         */
-#if defined(_MSC_VER) && (_MSC_VER < 1916)
-        QL_DEPRECATED
-#else
         [[deprecated("Use one of the constructors taking shared_ptr.")]]
-#endif
         explicit RelinkableHandle(
                        T* p,
                        bool registerAsObserver = true);