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Author: serhiy-storchaka

Include/pymacro.h

@@ -115,8 +115,13 @@
 #define Py_MAX(x, y) (((x) > (y)) ? (x) : (y))
 
 /* Absolute value of the number x */
-#define _Py_ABS_CAST(T,x) ((x) >= 0 ? ((T) (x)) : (- (((T) ((x) + 1)) - 1)))
 #define Py_ABS(x) ((x) < 0 ? -(x) : (x))
+/* Safer implementation that avoids an undefined behavior for the minimal
+   value of the signed integer type if its absolute value is larger than
+   the maximal value of the signed integer type (in the two's complement
+   representations, which is common).
+ */
+#define _Py_ABS_CAST(T, x) ((x) >= 0 ? ((T) (x)) : ((T) (((T) -((x) + 1)) + 1u)))
 
 #define _Py_XSTRINGIFY(x) #x