From 549033f3a2a4c31ca6443dc3208e6dedae8aa943 Mon Sep 17 00:00:00 2001 From: Francois-Xavier Coudert Date: Thu, 8 Jun 2006 23:48:05 +0200 Subject: [PATCH] re PR fortran/27958 (assignments to and from zero-sized string selections not handled) PR fortran/27958 * trans-expr.c (gfc_conv_substring): If the substring start is greater than its end, the length of the substring is zero, and not negative. (gfc_trans_string_copy): Don't generate a call to _gfortran_copy_string when destination length is zero. * gcc/testsuite/gfortran.dg/substr_2.f: New test. From-SVN: r114496 --- gcc/fortran/ChangeLog | 9 +++++++++ gcc/fortran/trans-expr.c | 7 +++++++ gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gfortran.dg/substr_2.f | 24 ++++++++++++++++++++++++ 4 files changed, 45 insertions(+) create mode 100644 gcc/testsuite/gfortran.dg/substr_2.f diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog index e2a4aafa243..0a3d2c12bee 100644 --- a/gcc/fortran/ChangeLog +++ b/gcc/fortran/ChangeLog @@ -1,3 +1,12 @@ +2006-06-08 Francois-Xavier Coudert + + PR fortran/27958 + * trans-expr.c (gfc_conv_substring): If the substring start is + greater than its end, the length of the substring is zero, and + not negative. + (gfc_trans_string_copy): Don't generate a call to + _gfortran_copy_string when destination length is zero. + 2006-06-08 Asher Langton PR fortran/27786 diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c index c0422b1aaf8..9e5524f09c3 100644 --- a/gcc/fortran/trans-expr.c +++ b/gcc/fortran/trans-expr.c @@ -275,6 +275,8 @@ gfc_conv_substring (gfc_se * se, gfc_ref * ref, int kind) build_int_cst (gfc_charlen_type_node, 1), start.expr); tmp = fold_build2 (PLUS_EXPR, gfc_charlen_type_node, end.expr, tmp); + tmp = fold_build2 (MAX_EXPR, gfc_charlen_type_node, tmp, + build_int_cst (gfc_charlen_type_node, 0)); se->string_length = tmp; } @@ -2196,6 +2198,7 @@ gfc_trans_string_copy (stmtblock_t * block, tree dlen, tree dest, tree tmp; tree dsc; tree ssc; + tree cond; /* Deal with single character specially. */ dsc = gfc_to_single_character (dlen, dest); @@ -2206,12 +2209,16 @@ gfc_trans_string_copy (stmtblock_t * block, tree dlen, tree dest, return; } + cond = fold_build2 (GT_EXPR, boolean_type_node, dlen, + build_int_cst (gfc_charlen_type_node, 0)); + tmp = NULL_TREE; tmp = gfc_chainon_list (tmp, dlen); tmp = gfc_chainon_list (tmp, dest); tmp = gfc_chainon_list (tmp, slen); tmp = gfc_chainon_list (tmp, src); tmp = build_function_call_expr (gfor_fndecl_copy_string, tmp); + tmp = fold_build3 (COND_EXPR, void_type_node, cond, tmp, build_empty_stmt ()); gfc_add_expr_to_block (block, tmp); } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index a5455d99d9a..53c280a0dbf 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2006-06-08 Francois-Xavier Coudert + + PR fortran/27958 + * gcc/testsuite/gfortran.dg/substr_2.f: New test. + 2006-06-08 Asher Langton PR fortran/27786 diff --git a/gcc/testsuite/gfortran.dg/substr_2.f b/gcc/testsuite/gfortran.dg/substr_2.f new file mode 100644 index 00000000000..a7e43b635e8 --- /dev/null +++ b/gcc/testsuite/gfortran.dg/substr_2.f @@ -0,0 +1,24 @@ +! { dg-do run } +! Check that substrings behave correctly even when zero-sized + implicit none + character(len=10) :: s, t + integer :: i, j + + s = "abcdefghij" + t(:10) = s(1:) + s(6:5) = "foo" + if (s /= t) call abort + i = 2 + j = -1 + s(i:i+j) = "foo" + if (s /= t) call abort + i = 20 + s(i+1:i) = "foo" + if (s /= t) call abort + s(6:5) = s(7:5) + if (s /= t) call abort + s = t(7:6) + if (len(trim(s)) /= 0) call abort + if (len(t(8:4)) /= 0) call abort + if (len(trim(t(8:4))) /= 0) call abort + end