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+# C++ Scratchpad
+
+## New features in C++
+
+- 23 and 26
+- r-value (and the values that I forgor)
+
+## Patterns
+
+- CRTP
+
+## compiler options that make undefined an error
+
+- -fsanitize=undefined
+- chk_add(), chkd_sub(), chkd_mul()
+- non-portable ways to check CPU overflow
+  - msvc intsafe.h
+
+## Design Patterns