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[patch, fortran] Add warning for creation of array temporaries
- From: Thomas Koenig <tkoenig at netcologne dot de>
- To: fortran at gcc dot gnu dot org
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Wed, 23 Jul 2008 15:15:21 +0200
- Subject: [patch, fortran] Add warning for creation of array temporaries
Hello world,
this patch adds a warning flag for the creation of array temporaries, as
a possible aid to optimization. All calls to internal_pack are also
flagged.
This isn't exactly what PR 29952 is about, because this is compile- time
instead of run-time, but I thought it was close enough to mention the PR
int che ChangeLog anyway.
Regression-tested on i686-pc-linux-gnu. Doc changes tested with "make
info" and "make dvi".
OK for trunk?
Thomas
2008-07-23 Thomas Koenig <tkoenig@gcc.gnu.org>
PR fortran/29952
* gfortran.h: Add "warn_array_temp" to gfc_option_t.
* lang.opt: Add -Warray-temporaries.
* invoke.texi: Document -Warray-temporaries
* trans-array.h (gfc_trans_create_temp_array): Add argument of
type *locus.
(gfc_conv_loop_setup): Likewise.
* trans-array.c (gfc_trans_create_temp_array): If
-Warray-temporaries is given and locus is present, warn about
creation of array temporaries.
(gfc_trans_array_constructor_subarray): Add locus to call
of gfc_conv_loop_setup.
(gfc_trans_array_constructor): Add where argument. Pass where
argument to call of gfc_trans_create_temp_array.
(gfc_add_loop_ss_code): Add where argument. Pass where argument
to recurrsive call of gfc_add_loop_ss_code and to call of
gfc_trans_array_constructor.
(gfc_conv_loop_setup): Add where argument. Pass where argument
to calls to gfc_add_loop_ss_code and to gfc_trans_create_temp_array.
(gfc_conv_expr_descriptor): Pass location to call of
gfc_conv_loop_setup.
(gfc_conv_array_parameter): If -Warray-temporaries is given,
warn about creation of temporary arrays.
* trans-expr.c (gfc_conv_subref_array_arg): Add where argument
to call to gfc_conv_loop_setup.
(gfc_conv_function_call): Add where argument to call to
gfc_trans_creat_temp_array.
(gfc_trans_subarray_assign): Likewise.
(gfc_trans_assignment_1): Add where argument to call to
gfc_conv_loop_setup.
* trans-stmt.c (gfc_conv_elemental_dependencies): Add where
argument to call to gfc_trans_create_temp_array.
(gfc_trans_call): Add where argument to call to gfc_conv_loop_setup.
(generate_loop_for_temp_to_lhs): Likewise.
(generate_loop_for_rhs_to_temp): Likewise.
(compute_inner_temp_size): Likewise.
(gfc_trans-pointer_assign_need_temp): Likewise.
(gfc_evaluate_where_mask): Likewise.
(gfc_trans_where_assign): Likewise.
(gfc_trans_where_3): Likewise.
* trans-io.c (transfer_srray_component): Add where argument
to function. Add where argument to call to gfc_conv_loop_setup.
(transfer_expr): Add where argument to call to
transfer_array_component.
(gfc_trans_transfer): Add where expression to call to
gfc_conv_loop_setup.
* trans-intrinsic.c (gfc_conv_intrinsic_anyall): Add
where argument to call to gfc_conv_loop_setup.
(gfc_conv_intrinsic_count): Likewise.
(gfc_conv_intrinsic_arith): Likewise.
(gfc_conv_intrinsic_dot_product): Likewise.
(gfc_conv_intrinsic_minmaxloc): Likewise.
(gfc_conv_intrinsic_minmaxval): Likewise.
(gfc_conv_intrinsic_array_transfer): Warn about
creation of temporary array.
Add where argument to call to gfc_trans_create_temp_array.
* options.c (gfc_init_options): Initialize gfc_option.warn_array_temp.
(gfc_handle_option): Set gfc_option.warn_array_temp.
2008-07-23 Thomas Koenig <tkoenig@gcc.gnu.org>
PR fortran/29952
* gfortran.dg/array_temporaries_1.f90: New test case.
Index: trans-array.c
===================================================================
--- trans-array.c (revision 138022)
+++ trans-array.c (working copy)
@@ -576,7 +576,7 @@ tree
gfc_trans_create_temp_array (stmtblock_t * pre, stmtblock_t * post,
gfc_loopinfo * loop, gfc_ss_info * info,
tree eltype, bool dynamic, bool dealloc,
- bool callee_alloc)
+ bool callee_alloc, locus * where)
{
tree type;
tree desc;
@@ -589,6 +589,10 @@ gfc_trans_create_temp_array (stmtblock_t
int dim;
gcc_assert (info->dimen > 0);
+
+ if (gfc_option.warn_array_temp && where)
+ gfc_warning ("Creating array temporary at %L", where);
+
/* Set the lower bound to zero. */
for (dim = 0; dim < info->dimen; dim++)
{
@@ -1070,7 +1074,7 @@ gfc_trans_array_constructor_subarray (st
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
/* Make sure the constructed array has room for the new data. */
if (dynamic)
@@ -1683,7 +1687,7 @@ constant_array_constructor_loop_size (gf
simplest method. */
static void
-gfc_trans_array_constructor (gfc_loopinfo * loop, gfc_ss * ss)
+gfc_trans_array_constructor (gfc_loopinfo * loop, gfc_ss * ss, locus * where)
{
gfc_constructor *c;
tree offset;
@@ -1809,7 +1813,7 @@ gfc_trans_array_constructor (gfc_loopinf
loopfrom = NULL_TREE;
gfc_trans_create_temp_array (&loop->pre, &loop->post, loop, &ss->data.info,
- type, dynamic, true, false);
+ type, dynamic, true, false, where);
if (loopfrom != NULL_TREE)
{
@@ -1896,7 +1900,8 @@ gfc_set_vector_loop_bounds (gfc_loopinfo
but before the actual scalarizing loops. */
static void
-gfc_add_loop_ss_code (gfc_loopinfo * loop, gfc_ss * ss, bool subscript)
+gfc_add_loop_ss_code (gfc_loopinfo * loop, gfc_ss * ss, bool subscript,
+ locus * where)
{
gfc_se se;
int n;
@@ -1950,7 +1955,8 @@ gfc_add_loop_ss_code (gfc_loopinfo * loo
/* Add the expressions for scalar and vector subscripts. */
for (n = 0; n < GFC_MAX_DIMENSIONS; n++)
if (ss->data.info.subscript[n])
- gfc_add_loop_ss_code (loop, ss->data.info.subscript[n], true);
+ gfc_add_loop_ss_code (loop, ss->data.info.subscript[n], true,
+ where);
gfc_set_vector_loop_bounds (loop, &ss->data.info);
break;
@@ -1993,7 +1999,7 @@ gfc_add_loop_ss_code (gfc_loopinfo * loo
gfc_add_block_to_block (&loop->pre, &se.pre);
gfc_add_block_to_block (&loop->post, &se.post);
}
- gfc_trans_array_constructor (loop, ss);
+ gfc_trans_array_constructor (loop, ss, where);
break;
case GFC_SS_TEMP:
@@ -3327,7 +3333,7 @@ gfc_conv_resolve_dependencies (gfc_loopi
moved outside the loop. */
void
-gfc_conv_loop_setup (gfc_loopinfo * loop)
+gfc_conv_loop_setup (gfc_loopinfo * loop, locus * where)
{
int n;
int dim;
@@ -3493,7 +3499,7 @@ gfc_conv_loop_setup (gfc_loopinfo * loop
/* Add all the scalar code that can be taken out of the loops.
This may include calculating the loop bounds, so do it before
allocating the temporary. */
- gfc_add_loop_ss_code (loop, loop->ss, false);
+ gfc_add_loop_ss_code (loop, loop->ss, false, where);
/* If we want a temporary then create it. */
if (loop->temp_ss != NULL)
@@ -3515,7 +3521,7 @@ gfc_conv_loop_setup (gfc_loopinfo * loop
loop->temp_ss->data.info.dimen = n;
gfc_trans_create_temp_array (&loop->pre, &loop->post, loop,
&loop->temp_ss->data.info, tmp, false, true,
- false);
+ false, where);
}
for (n = 0; n < loop->temp_dim; n++)
@@ -4299,6 +4305,9 @@ gfc_trans_dummy_array_bias (gfc_symbol *
stmt_unpacked = build_call_expr (gfor_fndecl_in_pack, 1, tmp);
stride = gfc_index_one_node;
+
+ if (gfc_option.warn_array_temp)
+ gfc_warning ("Creating array temporary at %L", &loc);
}
/* This is for the case where the array data is used directly without
@@ -4871,7 +4880,7 @@ gfc_conv_expr_descriptor (gfc_se * se, g
gfc_add_ss_to_loop (&loop, loop.temp_ss);
}
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, & expr->where);
if (need_tmp)
{
@@ -5219,6 +5228,10 @@ gfc_conv_array_parameter (gfc_se * se, g
{
desc = se->expr;
/* Repack the array. */
+
+ if (gfc_option.warn_array_temp)
+ gfc_warning ("Creating array temporary at %L", &expr->where);
+
ptr = build_call_expr (gfor_fndecl_in_pack, 1, desc);
ptr = gfc_evaluate_now (ptr, &se->pre);
se->expr = ptr;
Index: trans-expr.c
===================================================================
--- trans-expr.c (revision 138022)
+++ trans-expr.c (working copy)
@@ -2059,7 +2059,7 @@ gfc_conv_subref_array_arg (gfc_se * parm
gfc_add_ss_to_loop (&loop, loop.temp_ss);
/* Setup the scalarizing loops. */
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
/* Pass the temporary descriptor back to the caller. */
info = &loop.temp_ss->data.info;
@@ -2124,7 +2124,7 @@ gfc_conv_subref_array_arg (gfc_se * parm
gfc_conv_ss_startstride (&loop2);
/* Setup the scalarizing loops. */
- gfc_conv_loop_setup (&loop2);
+ gfc_conv_loop_setup (&loop2, &expr->where);
gfc_copy_loopinfo_to_se (&lse, &loop2);
gfc_copy_loopinfo_to_se (&rse, &loop2);
@@ -2717,7 +2717,8 @@ gfc_conv_function_call (gfc_se * se, gfc
mustn't be deallocated. */
callee_alloc = sym->attr.allocatable || sym->attr.pointer;
gfc_trans_create_temp_array (&se->pre, &se->post, se->loop, info, tmp,
- false, !sym->attr.pointer, callee_alloc);
+ false, !sym->attr.pointer, callee_alloc,
+ &se->ss->expr->where);
/* Pass the temporary as the first argument. */
tmp = info->descriptor;
@@ -3335,7 +3336,7 @@ gfc_trans_subarray_assign (tree dest, gf
gfc_conv_ss_startstride (&loop);
/* Setup the scalarizing loops. */
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
/* Setup the gfc_se structures. */
gfc_copy_loopinfo_to_se (&lse, &loop);
@@ -4415,7 +4416,7 @@ gfc_trans_assignment_1 (gfc_expr * expr1
/* Resolve any data dependencies in the statement. */
gfc_conv_resolve_dependencies (&loop, lss, rss);
/* Setup the scalarizing loops. */
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr2->where);
/* Setup the gfc_se structures. */
gfc_copy_loopinfo_to_se (&lse, &loop);
Index: trans-array.h
===================================================================
--- trans-array.h (revision 138022)
+++ trans-array.h (working copy)
@@ -32,7 +32,8 @@ void gfc_set_loop_bounds_from_array_spec
/* Generate code to create a temporary array. */
tree gfc_trans_create_temp_array (stmtblock_t *, stmtblock_t *, gfc_loopinfo *,
- gfc_ss_info *, tree, bool, bool, bool);
+ gfc_ss_info *, tree, bool, bool, bool,
+ locus *);
/* Generate function entry code for allocation of compiler allocated array
variables. */
@@ -88,7 +89,7 @@ void gfc_trans_scalarizing_loops (gfc_lo
/* Mark the end of the main loop body and the start of the copying loop. */
void gfc_trans_scalarized_loop_boundary (gfc_loopinfo *, stmtblock_t *);
/* Initialize the scalarization loop parameters. */
-void gfc_conv_loop_setup (gfc_loopinfo *);
+void gfc_conv_loop_setup (gfc_loopinfo *, locus *);
/* Resolve array assignment dependencies. */
void gfc_conv_resolve_dependencies (gfc_loopinfo *, gfc_ss *, gfc_ss *);
/* Build a null array descriptor constructor. */
Index: gfortran.h
===================================================================
--- gfortran.h (revision 138022)
+++ gfortran.h (working copy)
@@ -1873,6 +1873,7 @@ typedef struct
int warn_tabs;
int warn_underflow;
int warn_character_truncation;
+ int warn_array_temp;
int max_errors;
int flag_all_intrinsics;
Index: lang.opt
===================================================================
--- lang.opt (revision 138022)
+++ lang.opt (working copy)
@@ -76,6 +76,10 @@ Wampersand
Fortran Warning
Warn about missing ampersand in continued character constants
+Warray-temporaries
+Fortran Warning
+Warn about creation of array temporaries
+
Wcharacter-truncation
Fortran Warning
Warn about truncated character expressions
Index: trans-stmt.c
===================================================================
--- trans-stmt.c (revision 138022)
+++ trans-stmt.c (working copy)
@@ -269,7 +269,8 @@ gfc_conv_elemental_dependencies (gfc_se
tmp = gfc_typenode_for_spec (&e->ts);
tmp = gfc_trans_create_temp_array (&se->pre, &se->post,
&tmp_loop, info, tmp,
- false, true, false);
+ false, true, false,
+ & arg->expr->where);
gfc_add_modify_expr (&se->pre, size, tmp);
tmp = fold_convert (pvoid_type_node, info->data);
gfc_add_modify_expr (&se->pre, data, tmp);
@@ -375,7 +376,7 @@ gfc_trans_call (gfc_code * code, bool de
gfc_add_ss_to_loop (&loop, ss);
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &code->expr->where);
gfc_mark_ss_chain_used (ss, 1);
/* Convert the arguments, checking for dependencies. */
@@ -1977,7 +1978,7 @@ generate_loop_for_temp_to_lhs (gfc_expr
/* Calculate the bounds of the scalarization. */
gfc_conv_ss_startstride (&loop1);
/* Setup the scalarizing loops. */
- gfc_conv_loop_setup (&loop1);
+ gfc_conv_loop_setup (&loop1, &expr->where);
gfc_mark_ss_chain_used (lss, 1);
@@ -2075,7 +2076,7 @@ generate_loop_for_rhs_to_temp (gfc_expr
gfc_add_ss_to_loop (&loop, rss);
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr2->where);
gfc_mark_ss_chain_used (rss, 1);
/* Start the loop body. */
@@ -2197,7 +2198,7 @@ compute_inner_temp_size (gfc_expr *expr1
flag_bounds_check = 0;
gfc_conv_ss_startstride (&loop);
flag_bounds_check = save_flag;
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr2->where);
/* Figure out how many elements we need. */
for (i = 0; i < loop.dimen; i++)
@@ -2538,7 +2539,7 @@ gfc_trans_pointer_assign_need_temp (gfc_
/* Setup the scalarizing loops and bounds. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr2->where);
info = &rss->data.info;
desc = info->descriptor;
@@ -3019,7 +3020,7 @@ gfc_evaluate_where_mask (gfc_expr * me,
gfc_add_ss_to_loop (&loop, rss);
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &me->where);
gfc_mark_ss_chain_used (rss, 1);
/* Start the loop body. */
@@ -3186,7 +3187,7 @@ gfc_trans_where_assign (gfc_expr *expr1,
gfc_conv_resolve_dependencies (&loop, lss_section, rss);
/* Setup the scalarizing loops. */
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr2->where);
/* Setup the gfc_se structures. */
gfc_copy_loopinfo_to_se (&lse, &loop);
@@ -3634,7 +3635,7 @@ gfc_trans_where_3 (gfc_code * cblock, gf
}
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &tdst->where);
gfc_mark_ss_chain_used (css, 1);
gfc_mark_ss_chain_used (tdss, 1);
Index: invoke.texi
===================================================================
--- invoke.texi (revision 138022)
+++ invoke.texi (working copy)
@@ -137,9 +137,9 @@ by type. Explanations are in the follow
and warnings}.
@gccoptlist{-fmax-errors=@var{n} @gol
-fsyntax-only -pedantic -pedantic-errors @gol
--Wall -Waliasing -Wampersand -Wcharacter-truncation -Wconversion @gol
--Wimplicit-interface -Wline-truncation -Wnonstd-intrinsics -Wsurprising @gol
--Wno-tabs -Wunderflow -Wunused-parameter}
+-Wall -Waliasing -Wampersand -Warray-bounds -Wcharacter-truncation @gol
+-Wconversion -Wimplicit-interface -Wline-truncation -Wnonstd-intrinsics @gol
+-Wsurprising -Wno-tabs -Wunderflow -Wunused-parameter}
@item Debugging Options
@xref{Debugging Options,,Options for debugging your program or GNU Fortran}.
@@ -698,6 +698,13 @@ given in a continued character constant,
at the first non-comment, non-whitespace character after the ampersand
that initiated the continuation.
+@item -Warray-temporaries
+@opindex @code{Warray-temporaries}
+@cindex warnings, array temporaries
+Warn about array temporaries generated by the compiler. The information
+generated by this warning is sometimes useful in optimization, to avoid
+such temporaties.
+
@item -Wcharacter-truncation
@opindex @code{Wcharacter-truncation}
@cindex warnings, character truncation
Index: trans-io.c
===================================================================
--- trans-io.c (revision 138022)
+++ trans-io.c (working copy)
@@ -1900,7 +1900,7 @@ transfer_expr (gfc_se * se, gfc_typespec
recursive. */
static tree
-transfer_array_component (tree expr, gfc_component * cm)
+transfer_array_component (tree expr, gfc_component * cm, locus * where)
{
tree tmp;
stmtblock_t body;
@@ -1944,7 +1944,7 @@ transfer_array_component (tree expr, gfc
gfc_init_loopinfo (&loop);
gfc_add_ss_to_loop (&loop, ss);
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, where);
gfc_mark_ss_chain_used (ss, 1);
gfc_start_scalarized_body (&loop, &body);
@@ -2089,7 +2089,7 @@ transfer_expr (gfc_se * se, gfc_typespec
if (c->dimension)
{
- tmp = transfer_array_component (tmp, c);
+ tmp = transfer_array_component (tmp, c, & code->loc);
gfc_add_expr_to_block (&se->pre, tmp);
}
else
@@ -2213,7 +2213,7 @@ gfc_trans_transfer (gfc_code * code)
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &code->expr->where);
/* The main loop body. */
gfc_mark_ss_chain_used (ss, 1);
Index: trans-intrinsic.c
===================================================================
--- trans-intrinsic.c (revision 138022)
+++ trans-intrinsic.c (working copy)
@@ -1731,7 +1731,7 @@ gfc_conv_intrinsic_anyall (gfc_se * se,
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
gfc_mark_ss_chain_used (arrayss, 1);
/* Generate the loop body. */
@@ -1813,7 +1813,7 @@ gfc_conv_intrinsic_count (gfc_se * se, g
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
gfc_mark_ss_chain_used (arrayss, 1);
/* Generate the loop body. */
@@ -1901,7 +1901,7 @@ gfc_conv_intrinsic_arith (gfc_se * se, g
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
gfc_mark_ss_chain_used (arrayss, 1);
if (maskss)
@@ -2019,7 +2019,7 @@ gfc_conv_intrinsic_dot_product (gfc_se *
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
gfc_mark_ss_chain_used (arrayss1, 1);
gfc_mark_ss_chain_used (arrayss2, 1);
@@ -2159,7 +2159,7 @@ gfc_conv_intrinsic_minmaxloc (gfc_se * s
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
gcc_assert (loop.dimen == 1);
@@ -2355,7 +2355,7 @@ gfc_conv_intrinsic_minmaxval (gfc_se * s
/* Initialize the loop. */
gfc_conv_ss_startstride (&loop);
- gfc_conv_loop_setup (&loop);
+ gfc_conv_loop_setup (&loop, &expr->where);
gfc_mark_ss_chain_used (arrayss, 1);
if (maskss)
@@ -3434,6 +3434,10 @@ gfc_conv_intrinsic_array_transfer (gfc_s
&& arg->expr->ref->u.ar.type == AR_FULL))
{
tmp = build_fold_addr_expr (argse.expr);
+
+ if (gfc_option.warn_array_temp)
+ gfc_warning ("Creating array temporary at %L", &expr->where);
+
source = build_call_expr (gfor_fndecl_in_pack, 1, tmp);
source = gfc_evaluate_now (source, &argse.pre);
@@ -3587,7 +3591,8 @@ gfc_conv_intrinsic_array_transfer (gfc_s
FIXME callee_alloc is not set! */
gfc_trans_create_temp_array (&se->pre, &se->post, se->loop,
- info, mold_type, false, true, false);
+ info, mold_type, false, true, false,
+ &expr->where);
/* Cast the pointer to the result. */
tmp = gfc_conv_descriptor_data_get (info->descriptor);
Index: options.c
===================================================================
--- options.c (revision 138022)
+++ options.c (working copy)
@@ -69,6 +69,7 @@ gfc_init_options (unsigned int argc, con
gfc_option.warn_aliasing = 0;
gfc_option.warn_ampersand = 0;
gfc_option.warn_character_truncation = 0;
+ gfc_option.warn_array_temp = 0;
gfc_option.warn_conversion = 0;
gfc_option.warn_implicit_interface = 0;
gfc_option.warn_line_truncation = 0;
@@ -485,6 +486,10 @@ gfc_handle_option (size_t scode, const c
gfc_option.warn_ampersand = value;
break;
+ case OPT_Warray_temporaries:
+ gfc_option.warn_array_temp = value;
+ break;
+
case OPT_Wcharacter_truncation:
gfc_option.warn_character_truncation = value;
break;
! { dg-do compile }
! { dg-options "-Warray-temporaries" }
subroutine bar(a)
real, dimension(2) :: a
end
program main
integer, parameter :: n=3
integer :: i
real, dimension(n) :: a, b
a = 0.2
i = 2
a(i:i+1) = a(1:2) ! { dg-warning "Creating array temporary" }
a = cshift(a,1) ! { dg-warning "Creating array temporary" }
b = cshift(a,1)
call bar(a(1:3:2)) ! { dg-warning "Creating array temporary" }
end program main