[PATCH] PR fortran/102520 - [10/11/12 Regression] ICE in expand_constructor, at fortran/array.c:1802

[Harald Anlauf via Gcc-patches]

Dear Fortranners,

Gerhard's testcase triggers a NULL pointer dereference during the
attempt to expand an invalid constructor.  The simple and obvious
solution is to catch that case.

Regtested on x86_64-pc-linux-gnu.  OK for all affected branches?

Thanks,
Harald


Fortran: fix error recovery for invalid constructor

gcc/fortran/ChangeLog:

	PR fortran/102520
	* array.c (expand_constructor): Do not dereference NULL pointer.

gcc/testsuite/ChangeLog:

	PR fortran/102520
	* gfortran.dg/pr102520.f90: New test.

diff --git a/gcc/fortran/array.c b/gcc/fortran/array.c
index b858bada18a..8d66e009f66 100644
--- a/gcc/fortran/array.c
+++ b/gcc/fortran/array.c
@@ -1798,6 +1805,9 @@ expand_constructor (gfc_constructor_base base)

       e = c->expr;

+      if (e == NULL)
+	return false;
+
       if (empty_constructor)
 	empty_ts = e->ts;

diff --git a/gcc/testsuite/gfortran.dg/pr102520.f90 b/gcc/testsuite/gfortran.dg/pr102520.f90
new file mode 100644
index 00000000000..1c98c185c17
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr102520.f90
@@ -0,0 +1,12 @@
+! { dg-do compile }
+! PR fortran/102520 - ICE in expand_constructor, at fortran/array.c:1802
+
+program p
+  type t
+  end type
+  type(t), parameter :: a(4)   = shape(1)         ! { dg-error "Incompatible" }
+  type(t), parameter :: b(2,2) = reshape(a,[2,2]) ! { dg-error "Incompatible" }
+  type(t), parameter :: c(2,2) = transpose(b)     ! { dg-error "Unclassifiable" }
+end
+
+! { dg-error "Different shape for array assignment" " " { target *-*-* } 7 }