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Subject: Re: [PATCH] Fortran: fix simplification of INDEX(str1,str2) [PR105691]
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To: Harald Anlauf <anlauf@gmx.de>, fortran <fortran@gcc.gnu.org>,
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From: Thomas Koenig <tkoenig@netcologne.de>
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Hello Harald,

> compile time simplification of INDEX(str1,str2,back=.true.) gave wrong
> results.  Looking at gfc_simplify_index, this appeared to be close to
> a complete mess, while the runtime library code - which was developed
> later - was a relief.
> 
> The solution is to use the runtime library code as template to fix this.
> I took the opportunity to change string index and length variables
> in gfc_simplify_index to HOST_WIDE_INT.
> 
> Regtested on x86_64-pc-linux-gnu.  OK for mainline?
> 
> As this is a wrong-code issue, would this qualify for backports to
> open branches?

OK for both.

Thanks for the patch!


Best regards

	Thomas