RealView® Developer Kit Compiler and Libraries Guide 3.4.23. Lvalues

3.4.23. Lvalues

GNU mode enables a more relaxed definition on what constitutes an lvalue when looking at comma expressions and ?: constructs. You can use compound expressions, conditional expressions, and casts as follows:

You can assign a compound expression:
```
(a, b) += x;
```
This is equivalent to:
```
temp = (a,b);
b = temp + x
```
This causes the ARM compiler to generate a warning, for example:
```
Warning:  #174-D: expression has no effect
```
You can get the address of a compound expression &(a, b). This is equivalent to (a, &b).
You can use conditional expressions, for example:
```
(a ? b : c) = a;
```
This picks b or c as the destination dependent on a.

Supported in GNU mode only.

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