Conflicting router patterns when built with Go 1.23

[stefanb]

What's wrong?

Conflicting patterns detected when built with Go 1.23

$ grafana-agent --version
  panic: pattern "GET /debug/pprof/" (registered at net/http/pprof/pprof.go:100) conflicts with pattern "/debug/pprof/delta_heap" (registered at github.com/grafana/pyroscope-go/godeltaprof@v0.1.7/http/pprof/pprof.go:24):
  	GET /debug/pprof/ matches fewer methods than /debug/pprof/delta_heap, but has a more general path pattern

Steps to reproduce

When runing the tests for Homebrew/homebrew-core#175310 the Grafana agent test failed with:

  ==> Testing grafana-agent
  ==> /opt/homebrew/Cellar/grafana-agent/0.41.1/bin/grafana-agent --version
  panic: pattern "GET /debug/pprof/" (registered at net/http/pprof/pprof.go:100) conflicts with pattern "/debug/pprof/delta_heap" (registered at github.com/grafana/pyroscope-go/godeltaprof@v0.1.7/http/pprof/pprof.go:24):
  	GET /debug/pprof/ matches fewer methods than /debug/pprof/delta_heap, but has a more general path pattern
  
  goroutine 1 [running]:
  net/http.(*ServeMux).register(...)
  	net/http/server.go:2805
  net/http.HandleFunc({0x14000074e70?, 0x10587ac8a?}, 0x107723ea0?)
  	net/http/server.go:2799 +0x9c
  net/http/pprof.init.0()
  	net/http/pprof/pprof.go:100 +0x94

System information

All, irrelevant

Software version

Grafana Agent v0.41.1

Configuration

No response

Logs

No response

[stefanb]

There were some changes in the routing patterns according to https://tip.golang.org/doc/go1.23#nethttppkgnethttp

The patterns used by ServeMux now allow one or more spaces or tabs after the method name. Previously, only a single space was permitted.

...but this should not cause such error.

[gizmoguy]

Fixed in https://github.com/grafana/pyroscope-go/releases/tag/godeltaprof%2Fv0.1.8 by grafana/pyroscope-go@edd64fd

[llamafilm]

I got a very similar error trying to run Grafana Alloy with go 1.23. It works fine with go 1.22.

goroutine 1 [running]:
net/http.(*ServeMux).register(...)
net/http/server.go:2797
net/http.HandleFunc({0x14001af9800?, 0x109b3a330?}, 0x10baec9c0?)
net/http/server.go:2791 +0x9c
net/http/pprof.init.0()
net/http/pprof/pprof.go:100 +0x94
panic: pattern "GET /debug/pprof/" (registered at net/http/pprof/pprof.go:100) conflicts with pattern "/debug/pprof/delta_heap" (registered at [github.com/grafana/pyroscope-go/](http://github.com/grafana/pyroscope-go/)[godeltaprof@v0.1.7](mailto:godeltaprof@v0.1.7)/http/pprof/pprof.go:24):
GET /debug/pprof/ matches fewer methods than /debug/pprof/delta_heap, but has a more general path pattern