From 190b030035d2030d52d0a6ad1a5846f606c1897b Mon Sep 17 00:00:00 2001
From: Stefan Uhrig <stefan.uhrig@sap.com>
Date: Wed, 12 Oct 2022 16:38:46 +0200
Subject: [PATCH] Fix some unreachable code and possible loss of data warnings

---
 src/odbc/Config.h                | 10 +++++++++-
 src/odbc/StringConverter.cpp     |  2 +-
 src/odbc/internal/charset/Utf8.h |  4 ++--
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/odbc/Config.h b/src/odbc/Config.h
index 374c2b6..994e5c4 100644
--- a/src/odbc/Config.h
+++ b/src/odbc/Config.h
@@ -23,7 +23,15 @@
 #    endif
 #endif
 //------------------------------------------------------------------------------
-#ifdef _WIN32
+#if defined(__clang__) || defined(__GNUC__)
+#    define ODBC_UNREACHABLE __builtin_unreachable()
+#elif defined(_MSC_VER)
+#    define ODBC_UNREACHABLE __assume(false)
+#else
+#    define ODBC_UNREACHABLE ((void)0)
+#endif
+//------------------------------------------------------------------------------
+#ifdef _MSC_VER
 #   pragma warning(disable: 4251 4275)
 #endif
 //------------------------------------------------------------------------------
diff --git a/src/odbc/StringConverter.cpp b/src/odbc/StringConverter.cpp
index fda92d6..a813e70 100644
--- a/src/odbc/StringConverter.cpp
+++ b/src/odbc/StringConverter.cpp
@@ -53,7 +53,7 @@ u16string StringConverter::utf8ToUtf16(const char* begin, const char* end)
         }
         else
         {
-            str.push_back(cp.second);
+            str.push_back(static_cast<char16_t>(cp.second));
         }
     }
 
diff --git a/src/odbc/internal/charset/Utf8.h b/src/odbc/internal/charset/Utf8.h
index ce7f1db..22b0000 100644
--- a/src/odbc/internal/charset/Utf8.h
+++ b/src/odbc/internal/charset/Utf8.h
@@ -52,7 +52,7 @@ inline bool isValidSequence(int len, const char* c)
         return ((c[0] & 0xF8) == 0xF0) && ((c[1] & 0xC0) == 0x80)
                && ((c[2] & 0xC0) == 0x80) && ((c[3] & 0xC0) == 0x80);
     }
-    assert(false);
+    ODBC_UNREACHABLE;
 }
 //------------------------------------------------------------------------------
 /**
@@ -121,7 +121,7 @@ inline char32_t decode(int len, const char* c)
     case 4:
         return decode4(c);
     }
-    assert(false);
+    ODBC_UNREACHABLE;
 }
 //------------------------------------------------------------------------------
 } // namespace utf8