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Coding Convention Messages
c001
⚠️ Found ${statement} with unchecked STAT in “${proc}”
✅ Please always check the content of the variable passed to STAT=
in the very next statement.
c002
⚠️ Module “${mod}” USEd without ONLY clause or not PRIVATE
✅ Please start every Fortran module with PRIVATE
to prevent accidental leakage of symbols.
This message can also appear when a module is used without an ONLY
clause. However, in that case the compiler warning -Wuse-without-only
will also be triggered.
c003
⚠️ Symbol “${var}” in procedure “${proc}” is IMPLICIT-SAVE
✅ Please either move the variable initialization to the routine body or add an explicit SAVE
attribute.
In Fortran, assigning a variable at declaration implicitly adds the SAVE attribute. As an unexpected consequence the variable gets persevered across subroutine invocations. In the C programming language these are called static variables.
c004
⚠️ Symbol “${var}” in procedure “${proc}” is IMPLICIT-TYPE
✅ Please start every Fortran module with IMPLICIT NONE
to disable implicit typing.
c005
⚠️ Symbol “${var}” in procedure “${proc}” is THREADPRIVATE
✅ Please don't use thread-private variables because they break easily.
The OpenMP standard guaranteed the persistence of thread-private variables only between consecutive parallel regions and only under very specific conditions. Since any subroutine can open a parallel regions (or might in the future) this construct is very brittle.
As a workaround simply allocate an array of size omp_get_max_threads()
.
c006
⚠️ OMP PARALLEL without DEFAULT(NONE) found in “${proc}”
✅ Please always include DEFAULT(NONE)
when opening an OpenMP parallel region to avoid sharing a variable accidentally.
c007
⚠️ Found CALL with NULL() as argument in procedure “${proc}”
c008
⚠️ Found ASSOCIATE statement after OMP PARALLEL in “${proc}”
✅ Please don't use ASSOCIATE inside an OpenMP parallel region because some compiler get it wrong.
See #2668 for details.
c012
⚠️ Found WRITE statement with hardcoded unit in “${proc}”
c013
⚠️ Found DEALLOCATE with STAT argument in “${proc}”
✅ Please don't STAT=
to DEALLOCATE
to ensure that the program stops after a failure.
A failed deallocation is always indicative of a bug (e.g. double free or segmentation fault) and the program should not continue afterwards.
c014
⚠️ Found FLOAT in “${proc}”
c015
⚠️ Found lossy conversion ${m.group(1)} without KIND argument in “${proc}”
c016
⚠️ Found type ${derived_type} without initializer
✅ Please add default initialization to every derived type, for example like this:
TYPE foo_type INTEGER :: my_int = -1 REAL(dp) :: my_real = 0.0_dp LOGICAL :: my_logical = .FALSE. CHARACTER(LEN=42) :: my_string = "" TYPE(bar_type) :: my_nested = bar_type() REAL(dp), DIMENSION(3,3) :: my_array = 0.0_dp REAL(dp), DIMENSION(:), POINTER :: my_pointer => NULL() REAL(dp), DIMENSION(:), ALLOCATABLE :: my_alloc ! Automatically initialized END TYPE foo_type TYPE bar_type INTEGER :: my_int = -1 END TYPE bar_type
c101
⚠️ Found CALL cp_fm_gemm in procedure “${proc}”
✅ Please don't call cp_fm_gemm
directly, but instead use parallel_gemm
from src/parallel_gemm_api.F.
It allows for switching between different implementation - in particular ScaLAPACK and COSMA.
c102
⚠️ Found CALL m_abort in procedure “${proc}”
✅ Please don't call m_abort
directly, but instead use the error handling macro CPABORT(“message”)
.
c103
⚠️ Found CALL mp_abort in procedure “${proc}”
✅ Please don't call mp_abort
directly, but instead use the error handling macro CPABORT(“message”)
.
c104
⚠️ Found CALL RANDOM_NUMBER in procedure “${proc}”
✅ Please don't call RANDOM_NUMBER
, but instead use src/common/parallel_rng_types.F.
c105
⚠️ Found CALL RANDOM_SEED in procedure “${proc}”
✅ Please don't call RANDOM_SEED
, but instead use src/common/parallel_rng_types.F.
c201
⚠️ Found GOTO statement in procedure “${proc}”
✅ Please don't use the GOTO
statement because it's harmful and dangerous.
c202
⚠️ Found FORALL statement in procedure “${proc}”
✅ Please don't use the FORALL
statement because it's deprecated since Fortran 2018.
c203
⚠️ Found OPEN statement in procedure “${proc}”
✅ Please don't call OPEN
directly, but instead use the wrappers from src/common/cp_files.F.
c204
⚠️ Found CLOSE statement in procedure “${proc}”
✅ Please don't call CLOSE
directly, but instead use the wrappers from src/common/cp_files.F.
c205
⚠️ Found STOP statement in procedure “${proc}”
✅ Please don't call STOP
directly, but instead use the error handling macro CPABORT(“message”)
.