Unreachable code is part of the source code of a program which can never be executed because there exists no control flow path to the code from the rest of the program.
Questions tagged [unreachable-code]
181 questions
10
votes
5 answers
C# Unreachable code detected
I'm getting a "Unreachable code detected" message in Visual Studio at the point i++ in my code below. Can you spot what I've done wrong?
try
{
RegistryKey OurKey = Registry.CurrentUser;
OurKey.CreateSubKey("Software\\Resources\\Shared");
…
Jamie
- 2,465
- 10
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- 31
9
votes
2 answers
Why does Rust allow code with the wrong return type, but only with a trailing semicolon?
Consider the following Rust code:
fn f() -> i32 {
loop {
println!("Infinite loop!");
}
println!("Unreachable");
}
This compiles (with a warning) and runs, despite the fact that the return type is wrong.
It would seem that the…
Caleb Stanford
- 453
- 2
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9
votes
2 answers
javascript switch break unreachable code detected
I have the following code
switch (attr.templateType) {
case 'text': return tpl_default; break;
case 'currency': return tpl_currency; break;
case 'percentage': return tpl_percentage; break;
case 'latlong': return…
user2062455
- 411
- 5
- 14
8
votes
3 answers
Why java does not detect unreachable catch block if I use multiple catch blocks?
Research following method:
static private void foo() {
try {
throw new FileNotFoundException();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
…
gstackoverflow
- 36,709
- 117
- 359
- 710
8
votes
1 answer
Avoid "Unreachable code" warning for preprocessor-dependent code
I'm trying to figure out if there's any way to avoid getting an "Unreachable code" warning for something that's caused by the preprocessor. I don't want to suppress all such warnings, only those which will be dependent on the preprocessor, e.g.
#if…
Darrel Hoffman
- 4,436
- 6
- 29
- 41
7
votes
2 answers
Ada suppress unreachable code or missing return
I have a tagged type that implements a number of functions. In one case I need one of these functions to instead enter an infinite loop. Unfortunately as far as I can tell there is no way for me to compile this such that it doesn't raise a warning.…
LambdaBeta
- 1,479
- 1
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- 25
7
votes
6 answers
How to handle "not all code paths return a value" when the logic of the function does ensure a return
I suppose the easiest way to explain is by a contrived example:
public static int Fail() {
var b = true;
if (b) {
return 0;
}
}
This code will not compile, and gives the error "not all code paths return a value," while we humans…
Brent
- 4,153
- 4
- 30
- 63
7
votes
4 answers
Unreachable code at constructor's closing brace
I'm working on an application built with VC9 and I've hit upon a warning I don't fully understand: why is there an "unreachable code" warning on the closing brace of the constructor?
The minimal testcase to reproduce the issue…
mrkj
- 3,041
- 19
- 24
6
votes
2 answers
Why unreachable code isn't an error in C++?
unreachable code is compile time error in languages like Java. But why it is just warning in C++ & C?
Consider following example:
#include
int f()
{
int a=3;
return a;
int b=6; // oops it is unreachable code
…
Destructor
- 14,123
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5
votes
3 answers
"Unreachable code detected" in MSIL or Native code
Does compiler compile "Unreachable Codes" in MSIL or Native code in run time?
Babak
- 3,716
- 6
- 39
- 56
5
votes
1 answer
Why is gcc emitting worse code with __builtin_unreachable?
With f0 and f1 as below,
long long b;
void f0(int a) {
a %= 10;
if (a == 0) b += 11;
else if (a == 1) b += 13;
else if (a == 2) b += 17;
else if (a == 3) b += 19;
else if (a == 4) b += 23;
else if (a == 5) b += 29;
…
user3810155
5
votes
0 answers
Why does a properly functioning Rust library fail with unreachable code error when compiled to WASM using wasm-bindgen?
Consider this library as a dependency:
[dependencies]
rustengine = "1.0.60"
Compile this tiny program against it:
use rustenginelib::uci::*;
fn main() {
let mut uci = create_default_uci();
uci.process_uci_command("perft…
easychessanimations
- 93
- 1
- 8
5
votes
3 answers
When does the condition "Unreachable Code" occur in Java?
When there is some statement written after the infinite loop, that statement becomes the unreachable code. For ex:
for(;;)
{
}
Sytem.out.println("Test-1"); //unreachable code
But I am facing some difficulty here.
Look at the two code snippets…
Vikas Mangal
- 821
- 3
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- 23
5
votes
4 answers
Unreachable code detected by using const variables
I have following code:
private const FlyCapture2Managed.PixelFormat f7PF = FlyCapture2Managed.PixelFormat.PixelFormatMono16;
public PGRCamera(ExamForm input, bool red, int flags, int drawWidth, int drawHeight) {
if (f7PF ==…
SinisterMJ
- 3,425
- 2
- 33
- 53
5
votes
3 answers
Visual C++ error: function must return a value
I am working on a multiplatform project, and some platforms have disabled features, and in the interface for those features, a common thing I do is something like this:
bool Foo::bar() const {
// disabled
abort();
}
GCC/LLVM do not require…
fbafelipe
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- 2
- 25
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