Looking at this Go panic message, let me break down what each part tells us:
## Panic Details
```
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x3c6da8a]
```
- **SIGSEGV**: Segmentation violation (accessing invalid memory)
- **code=0x1**: Indicates a protection violation (accessing unmapped memory)
- **addr=0x20**: The memory address being accessed (32 in decimal - very low address, suggesting nil pointer + small offset)
- **pc=0x3c6da8a**: Program counter - the instruction address where the crash occurred
## Stack Trace Arguments
```
github.com/lotus-web3/ribs/rbdeal.(*ribsStagingProvider).Upload(
0xc00092b9d0, // receiver: pointer to ribsStagingProvider struct
{0xc0010f9a08?, 0x1649da5?}, // likely an interface (pointer + type info)
0x1, // probably an integer parameter
0x4412e40?, // unknown type (could be pointer or large int)
0xc0009664f0 // likely a pointer parameter
)
```
## Key Clues to the Problem
1. **Low memory address (0x20)**: This strongly suggests accessing a field/method on a nil pointer. The offset of 32 bytes indicates it's trying to access a struct field or method that's 32 bytes into the struct.
2. **The `?` marks**: These indicate the Go runtime couldn't determine the exact values, often seen with interface types or when debugging info is incomplete.
3. **Location**: `/home/danny/ribs/rbdeal/external.go:150 +0x6a` - line 150 in external.go
## Likely Root Cause
The crash is almost certainly caused by:
- A nil pointer in one of the parameters passed to `Upload()`
- The receiver `ribsStagingProvider` itself having a nil field that's being accessed
- An interface parameter containing a nil concrete value
To debug this, you should:
1. Check line 150 in `external.go`
2. Add nil checks for all pointer parameters and struct fields being accessed
3. Verify that interface parameters contain non-nil concrete values
The low memory address (0x20) is the biggest clue - it's classic nil pointer dereference with a small offset.