Re: [PATCH] Fortran: different character lengths in array constructor [PR93289]
Am 01.02.25 um 21:49 schrieb Harald Anlauf:
So why must we be so tough?
Here's what I get from other compilers:
Intel, Nvidia, AMD flang: silent by default.
ifx -stand f18:
char_array_constructor_5.f90(11): warning #8208: If type specification
is omitted, each ac-value expression in the array constructor of type
CHARACTER must have the same length type parameters. ['ab']
print *, [str, "ab", "hjf333"] ! { dg-warning "must have the same length" }
---^
So no error, but Intel is known to often be on the loose side.
NAG: hard error.
That's what we get with -std=f*, too.
[PATCH] Fortran: different character lengths in array constructor [PR93289]
Dear all,
the attached patch downgrades different constant character lengths in an
array constructor from a GNU to a legacy extension, so that users get a
warning with -std=gnu. We continue to generate an error when standard
conformance is requested.
Regtested on x86_64-pc-linux-gnu (found one testcase where this
triggered... :)
OK for mainline?
Thanks,
Harald
From c2ab5fc3e4cc758ca00e1878394c8f1466462f84 Mon Sep 17 00:00:00 2001
From: Harald Anlauf
Date: Sat, 1 Feb 2025 19:14:21 +0100
Subject: [PATCH] Fortran: different character lengths in array constructor
[PR93289]
PR fortran/93289
gcc/fortran/ChangeLog:
* decl.cc (gfc_set_constant_character_len): Downgrade different
string lengths in character array constructor to legacy extension.
gcc/testsuite/ChangeLog:
* gfortran.dg/unlimited_polymorphic_1.f03: Pad element in character
array constructor to correct length.
* gfortran.dg/char_array_constructor_5.f90: New test.
---
gcc/fortran/decl.cc | 20 +--
.../gfortran.dg/char_array_constructor_5.f90 | 13
.../gfortran.dg/unlimited_polymorphic_1.f03 | 2 +-
3 files changed, 28 insertions(+), 7 deletions(-)
create mode 100644 gcc/testsuite/gfortran.dg/char_array_constructor_5.f90
diff --git a/gcc/fortran/decl.cc b/gcc/fortran/decl.cc
index 7954a845bc0..5a46658651a 100644
--- a/gcc/fortran/decl.cc
+++ b/gcc/fortran/decl.cc
@@ -1889,12 +1889,20 @@ gfc_set_constant_character_len (gfc_charlen_t len, gfc_expr *expr,
/* Apply the standard by 'hand' otherwise it gets cleared for
initializers. */
- if (check_len != -1 && slen != check_len
- && !(gfc_option.allow_std & GFC_STD_GNU))
- gfc_error_now ("The CHARACTER elements of the array constructor "
- "at %L must have the same length (%ld/%ld)",
- &expr->where, (long) slen,
- (long) check_len);
+ if (check_len != -1 && slen != check_len)
+ {
+ if (!(gfc_option.allow_std & GFC_STD_GNU))
+ gfc_error_now ("The CHARACTER elements of the array constructor "
+ "at %L must have the same length (%ld/%ld)",
+ &expr->where, (long) slen,
+ (long) check_len);
+ else
+ gfc_notify_std (GFC_STD_LEGACY,
+ "The CHARACTER elements of the array constructor "
+ "at %L must have the same length (%ld/%ld)",
+ &expr->where, (long) slen,
+ (long) check_len);
+ }
s[len] = '\0';
free (expr->value.character.string);
diff --git a/gcc/testsuite/gfortran.dg/char_array_constructor_5.f90 b/gcc/testsuite/gfortran.dg/char_array_constructor_5.f90
new file mode 100644
index 000..0cbe6b1468d
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/char_array_constructor_5.f90
@@ -0,0 +1,13 @@
+! { dg-do compile }
+! { dg-additional-options "-std=gnu" }
+!
+! PR fortran/93289
+!
+! Contributed by Tobias Burnus
+
+character(len=*), parameter :: str = "abj", str2 = "1234"
+print *, [character(5) :: str, "ab", "hjf333"]
+print *, [character(5) :: str, str2]
+print *, [str, "ab", "hjf333"] ! { dg-warning "must have the same length" }
+print *, [str, str2]! { dg-warning "must have the same length" }
+end
diff --git a/gcc/testsuite/gfortran.dg/unlimited_polymorphic_1.f03 b/gcc/testsuite/gfortran.dg/unlimited_polymorphic_1.f03
index 8634031ad81..51483ed0332 100644
--- a/gcc/testsuite/gfortran.dg/unlimited_polymorphic_1.f03
+++ b/gcc/testsuite/gfortran.dg/unlimited_polymorphic_1.f03
@@ -155,7 +155,7 @@ END MODULE
call foo([a(8),a(9)], res)
if (trim (res) .ne. "type(a) array 8 9") STOP 1
- call foo([sun, " & rain"], res)
+ call foo([sun, " & rain "], res)
if (trim (res) .ne. "char( 8, 2)sunshine & rain") STOP 1
call foo([sun//" never happens", " & rain always happens"], res)
--
2.43.0
Re: [PATCH] Fortran: different character lengths in array constructor [PR93289]
Am 01.02.25 um 21:03 schrieb Steve Kargl: On Sat, Feb 01, 2025 at 07:25:51PM +0100, Harald Anlauf wrote: the attached patch downgrades different constant character lengths in an array constructor from a GNU to a legacy extension, so that users get a warning with -std=gnu. We continue to generate an error when standard conformance is requested. Regtested on x86_64-pc-linux-gnu (found one testcase where this triggered... :) OK for mainline? My vote is 'no'. This is either a GNU extension or an error. It is certainly not a legacy issue as array constructors simple cannot appear old moldy *legacy* codes. legacy /= moldy. My intention is to downgrade existing, potentially dangerous GNU extensions (like this one) carefully to "legacy", but not with an axe. I would be in favor of making it a hard error. If you believe gfortan must be able to compile invalid source, then add an option such as -fallow-invalid-scalar-character-entities-in-array-constructor. I don't see why we shall scare users by making code that is currently accepted silently, because it is a GNU extension, suddenly to a hard error. So why must we be so tough? $0.02
Re: [PATCH] Fortran: different character lengths in array constructor [PR93289]
On 2/1/25 10:25 AM, Harald Anlauf wrote: Dear all, the attached patch downgrades different constant character lengths in an array constructor from a GNU to a legacy extension, so that users get a warning with -std=gnu. We continue to generate an error when standard conformance is requested. Regtested on x86_64-pc-linux-gnu (found one testcase where this triggered... :) OK for mainline? Thanks, Harald Yes, OK, and thanks Jerry
Re: [PATCH] Fortran: different character lengths in array constructor [PR93289]
On Sat, Feb 01, 2025 at 07:25:51PM +0100, Harald Anlauf wrote: > > the attached patch downgrades different constant character lengths in an > array constructor from a GNU to a legacy extension, so that users get a > warning with -std=gnu. We continue to generate an error when standard > conformance is requested. > > Regtested on x86_64-pc-linux-gnu (found one testcase where this > triggered... :) > > OK for mainline? > My vote is 'no'. This is either a GNU extension or an error. It is certainly not a legacy issue as array constructors simple cannot appear old moldy *legacy* codes. I would be in favor of making it a hard error. If you believe gfortan must be able to compile invalid source, then add an option such as -fallow-invalid-scalar-character-entities-in-array-constructor. $0.02 -- Steve
Re: [PATCH] Fortran: different character lengths in array constructor [PR93289]
On Sat, Feb 01, 2025 at 09:49:17PM +0100, Harald Anlauf wrote: > Am 01.02.25 um 21:03 schrieb Steve Kargl: > > On Sat, Feb 01, 2025 at 07:25:51PM +0100, Harald Anlauf wrote: > > > > > > the attached patch downgrades different constant character lengths in an > > > array constructor from a GNU to a legacy extension, so that users get a > > > warning with -std=gnu. We continue to generate an error when standard > > > conformance is requested. > > > > > > Regtested on x86_64-pc-linux-gnu (found one testcase where this > > > triggered... :) > > > > > > OK for mainline? > > > > > > > My vote is 'no'. > > > > This is either a GNU extension or an error. It is certainly > > not a legacy issue as array constructors simple cannot appear > > old moldy *legacy* codes. > > legacy /= moldy. > > My intention is to downgrade existing, potentially dangerous > GNU extensions (like this one) carefully to "legacy", but not > with an axe. > > > I would be in favor of making it a hard error. If you believe > > gfortan must be able to compile invalid source, then add an option > > such as -fallow-invalid-scalar-character-entities-in-array-constructor. > > I don't see why we shall scare users by making code that is currently > accepted silently, because it is a GNU extension, suddenly to a hard > error. > > So why must we be so tough? > Because -std=legacy allows a whole bunch of garbage. Instead of fixing broken code, a user will slap -std=legacy in a Makefile and move on. Then years from now, you'll see -std=legacy in a whole bunch of Makefiles whether it is needed or not. See -maligned-double and -fallow-argument-mismatch as poster children. Removing these types of extensions and legacy features will hopefully make gfortran easier to maintain. Again, just my $0.02. -- Steve
Re: [PATCH] Fortran: different character lengths in array constructor [PR93289]
On 2/1/25 12:49 PM, Harald Anlauf wrote: Am 01.02.25 um 21:03 schrieb Steve Kargl: On Sat, Feb 01, 2025 at 07:25:51PM +0100, Harald Anlauf wrote: the attached patch downgrades different constant character lengths in an array constructor from a GNU to a legacy extension, so that users get a warning with -std=gnu. We continue to generate an error when standard conformance is requested. Regtested on x86_64-pc-linux-gnu (found one testcase where this triggered... :) OK for mainline? My vote is 'no'. This is either a GNU extension or an error. It is certainly not a legacy issue as array constructors simple cannot appear old moldy *legacy* codes. legacy /= moldy. My intention is to downgrade existing, potentially dangerous GNU extensions (like this one) carefully to "legacy", but not with an axe. I would be in favor of making it a hard error. If you believe gfortan must be able to compile invalid source, then add an option such as -fallow-invalid-scalar-character-entities-in-array-constructor. I don't see why we shall scare users by making code that is currently accepted silently, because it is a GNU extension, suddenly to a hard error. So why must we be so tough? $0.02 What do other compilers do? Do they reject it outright? --
