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Silence the warning: `Non-conforming tab character` in gfortran


I usually run my code with ifort, but during implementation, I prefer compiling and testing with gfortran as I find it to be a lot stricter than its intel counterpart.

While turning on compiling options such as -Wall, I get the following warning:

Warning: Nonconforming tab character at (1)

Is there a way to silence this one particular warning while using the same compiling options? Note that I do NOT want to replace tabs with space characters. If there is no way to resolve this issue, then the answer "No it's not possible" would suffice.


Solution

  • Warning: the below answer I originally wrote only applies to gfortran 4.x. The behaviour has been reversed in version 5.x, see the answer by DrOli.


    What have you tried so far? Does -Wtabs help? From man gfortran:

    -Wtabs

    By default, tabs are accepted as whitespace, but tabs are not members of the Fortran Character Set. For continuation lines, a tab followed by a digit between 1 and 9 is supported. -Wno-tabs will cause a warning to be issued if a tab is encountered. Note, -Wno-tabs is active for -pedantic, -std=f95, -std=f2003, -std=f2008 and -Wall.

    And -Wall sets -Wno-tabs.

    If it doesn't help, it could still be that -Wall overwrites this option. Then you can try manually setting -Wall without the tabs part:

    -Wall

    Enables commonly used warning options pertaining to usage that we recommend avoiding and that we believe are easy to avoid. This currently includes -Waliasing, -Wampersand, -Wconversion, -Wsurprising, -Wc-binding-type, -Wintrinsics-std, -Wno-tabs, -Wintrinsic-shadow, -Wline-truncation, -Wtarget-lifetime, -Wreal-q-constant and -Wunused.