Null passed to a callee that requires a non-null argument

[Liuyao_Zhang]

Dear Rooters:

I try to get a TH2D named “Bh2_Deta_Dphi_%d” from a root file.
However, it failed and get a warning that
null passed to a callee that requires a non-null argument [-Wnonnull]
Strangely, for the TH2D name “Sh2_Deta_Dphi_%i”, it works.
I posted the codes and corresponding input root file.
Looking forward to your help.

Best wishes
Liuyao

file.root (441.5 KB) test.C (679 Bytes)

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[dastudillo]

In the code you uploaded what doesn’t work is actually the Sh2 part, but not because of the name; you are trying to Add to h2S[i] when it has not been created, unlike h2B[i]. This works, for instance:

  for(int k=0; k<nfile; k++){
    h2S[k] = new TH2D(Form("h2S_%d",k), Form("h2S_%d", k), 100,-1.6,1.6,200,-1.5,2.*PI-1.5);
    h2B[k] = new TH2D(Form("h2B_%d",k), Form("h2B_%d", k), 100,-1.6,1.6,200,-1.5,2.*PI-1.5);
  }

[Liuyao_Zhang]

Dear dastudillo,

Sorry for my ignore. Actually, In the original version, h2S[i] also has been created.
I checked the code, and find the problem will occur when the code like
below:
sprintf(finName,"%s/result_%s.root", chose1[ic], chose2[ic]); fin[ic] = new TFile(finName,"READ");

When I try to change into
fin[ic] = new TFile(Form("%s/result_%s.root", chose1[ic], chose2[ic]),"READ"); or
fin[ic] = TFile::Open("./file.root");
`
The problem will be resolved.

I am not sure where the problem coming from?
There is something different?
or become the write and read of root file, I use the
different version, I used the 5.34 version to write root file,
and 6.22 to read.

[eguiraud]

Hi,
if

sprintf(finName,"%s/result_%s.root", chose1[ic], chose2[ic]);
fin[ic] = new TFile(finName,"READ");

doesn’t work but

fin[ic] = new TFile(Form("%s/result_%s.root", chose1[ic], chose2[ic]),"READ");

works, then I guess that finName results in a wrong filename in the first case.
You could print it to check what its value is. You should also check the value of fin[ic].IsZombie(): if it’s true, the file was not opened correctly.

The problem does not seem to be related to the ROOT version used.

Cheers,
Enrico