[RFA] Bug 58200 - Option fcheck is misleadingly located in option descriptions

[Dominique d'Humières]

Since I have taken this PR, I did not find any simple satisfactory solution. The present section 2.9 is an aggregate of unrelated options and the closest fix I came to would be to replace "Options for code generation conventions" with "Other options for code generation".

The present organisation is

	• 2 GNU Fortran Command Options
		• 2.1 Option summary
		• 2.2 Options controlling Fortran dialect
		• 2.3 Enable and customize preprocessing
		• 2.4 Options to request or suppress errors and warnings
		• 2.5 Options for debugging your program or GNU Fortran
		• 2.6 Options for directory search
		• 2.7 Influencing the linking step
		• 2.8 Influencing runtime behavior
		• 2.9 Options for code generation conventions
		• 2.10 Options for interoperability with other languages
		• 2.11 Environment variables affecting gfortran

The first step I am proposing is to change it to

	• 2 GNU Fortran Command Options
		• 2.1 Option summary
		• 2.2 Options controlling Fortran dialect
		• 2.3 Enable and customize preprocessing
		• 2.4 Frontend optimizations
			from present 2.9
			-ffrontend-optimize
			-ffrontend-loop-interchange
			-faggressive-function-elimination
			-fexternal-blas
			-fblas-matmul-limit=n
			-finline-matmul-limit=n
		• 2.5 Options changing the kind of variables
			from present 2.2 and changing the order
			-finteger-4-integer-8
			-freal-*
			-fdefault-integer-8
			-fdefault-real-*
		• 2.6 Options to request or suppress errors and warnings
		• 2.7 Options for debugging your program or GNU Fortran
		• 2.8 Options enabling runtime diagnostics
			from present 2.9
			-fcheck=<keyword>
			-fbounds-check
			-fcheck-array-temporaries
			-finit-*
			-frealloc-lhs (?)
			from present 2.5
			-ffpe-trap=list
			-ffpe-summary=list
			-fno-backtrace
		• 2.9 Options for directory search
		• 2.10 Influencing the linking step
		• 2.11 Influencing runtime behavior
		• 2.12 Options for code generation conventions
		• 2.13 Options for interoperability with other languages
		• 2.14 Environment variables affecting gfortran

As a second improvement, would be to rename 2.11 to something such as "Influencing I/O behavior", delete the 2.14 entry after moving its content to 2.11, and rename 2.7 to "Options for debugging GNU Fortran" and moving it to the last entry.

Waiting for comments.

Dominique