[PATCH] PR fortran/67804 - ICE on data initialization of type(character) with wrong data

[Harald Anlauf <anlauf@gmx.de>]

[-- Attachment #1: Type: text/plain, Size: 345 bytes --]

Dear Fortranners,

the attached patch improves error recovery after an invalid
structure constructor has been detected in a DATA statement.

Testcase by Gerhard.

Regtested on x86_64-pc-linux-gnu.  OK for mainline?

This should be a rather safe patch which I would like to
backport to 11-branch after a suitable waiting period.

Thanks,
Harald


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-Fortran-fix-error-recovery-on-bad-structure-construc.patch --]
[-- Type: text/x-patch, Size: 3366 bytes --]

From 31436189cb28590407030000ec6baff816cd63ef Mon Sep 17 00:00:00 2001
From: Harald Anlauf <anlauf@gmx.de>
Date: Wed, 12 Jan 2022 21:24:49 +0100
Subject: [PATCH] Fortran: fix error recovery on bad structure constructor in
 DATA statement

gcc/fortran/ChangeLog:

	PR fortran/67804
	* primary.c (gfc_match_structure_constructor): Recover from errors
	that occurred while checking for a valid structure constructor in
	a DATA statement.

gcc/testsuite/ChangeLog:

	PR fortran/67804
	* gfortran.dg/pr93604.f90: Adjust to changed diagnostics.
	* gfortran.dg/pr67804.f90: New test.
---
 gcc/fortran/primary.c                 | 15 ++++++++++++---
 gcc/testsuite/gfortran.dg/pr67804.f90 | 25 +++++++++++++++++++++++++
 gcc/testsuite/gfortran.dg/pr93604.f90 |  2 +-
 3 files changed, 38 insertions(+), 4 deletions(-)
 create mode 100644 gcc/testsuite/gfortran.dg/pr67804.f90

diff --git a/gcc/fortran/primary.c b/gcc/fortran/primary.c
index fd4d6af50c0..3f01f67cd49 100644
--- a/gcc/fortran/primary.c
+++ b/gcc/fortran/primary.c
@@ -3364,6 +3364,7 @@ gfc_match_structure_constructor (gfc_symbol *sym, gfc_expr **result)
   match m;
   gfc_expr *e;
   gfc_symtree *symtree;
+  bool t = true;

   gfc_get_ha_sym_tree (sym->name, &symtree);

@@ -3394,10 +3395,18 @@ gfc_match_structure_constructor (gfc_symbol *sym, gfc_expr **result)
      in the structure constructor must be a constant.  Try to reduce the
      expression here.  */
   if (gfc_in_match_data ())
-    gfc_reduce_init_expr (e);
+    t = gfc_reduce_init_expr (e);

-  *result = e;
-  return MATCH_YES;
+  if (t)
+    {
+      *result = e;
+      return MATCH_YES;
+    }
+  else
+    {
+      gfc_free_expr (e);
+      return MATCH_ERROR;
+    }
 }


diff --git a/gcc/testsuite/gfortran.dg/pr67804.f90 b/gcc/testsuite/gfortran.dg/pr67804.f90
new file mode 100644
index 00000000000..e2009a5bfdb
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr67804.f90
@@ -0,0 +1,25 @@
+! { dg-do compile }
+! PR fortran/67804 - ICE on bad type in structure constructor in DATA statement
+! Contributed by G.Steinmetz
+
+program p
+  type t
+     character :: c
+  end type
+  type u
+     character, pointer :: c
+  end type
+  type(t) :: x0, x1, x2, x3, x4, x5, x6, x7, x8, x9
+  type(u) :: y6
+  data x0 /t('a')/     ! OK
+  data x1 /t(1)/       ! { dg-error "Cannot convert" }
+  data x2 /t(1.)/      ! { dg-error "Cannot convert" }
+  data x3 /t(1d1)/     ! { dg-error "Cannot convert" }
+  data x4 /t((0.,1.))/ ! { dg-error "Cannot convert" }
+  data x5 /t(.true.)/  ! { dg-error "Cannot convert" }
+  data x6 /t(null())/  ! { dg-error "neither a POINTER nor ALLOCATABLE" }
+  data x7 /t(['1'])/   ! { dg-error "The rank of the element" }
+  data x8 /t([1])/     ! { dg-error "Cannot convert" }
+  data x9 /t(z'0')/    ! { dg-error "Cannot convert" }
+  data y6 /u(null())/  ! OK
+end
diff --git a/gcc/testsuite/gfortran.dg/pr93604.f90 b/gcc/testsuite/gfortran.dg/pr93604.f90
index 2c695d37829..4040155120c 100644
--- a/gcc/testsuite/gfortran.dg/pr93604.f90
+++ b/gcc/testsuite/gfortran.dg/pr93604.f90
@@ -5,6 +5,6 @@ program p
       integer :: a
    end type
    type(t) :: x
-   data x /t(z'1')/ ! { dg-error "cannot appear in a structure constructor" }
+   data x /t(z'1')/ ! { dg-error "BOZ" }
 end

--
2.31.1