From daf8c6f03b7b7ae33e2e8e301d367eb8cce80e5c Mon Sep 17 00:00:00 2001
From: Daniel Franke <franke.daniel@gmail.com>
Date: Wed, 19 May 2010 12:35:34 -0400
Subject: [PATCH] re PR fortran/44055 (Warn (-Wconversion*) when converting
single to double precision)
gcc/fortran/:
2010-05-19 Daniel Franke <franke.daniel@gmail.com>
PR fortran/44055
* lang.opt (Wconversion-extra): New option.
* gfortran.h (gfc_option_t): Add warn_conversion_extra.
* options.c (gfc_init_options): Disable -Wconversion-extra by default.
(set_Wall): Enable -Wconversion.
(gfc_handle_option): Set warn_conversion_extra.
* intrinsic.c (gfc_convert_type_warn): Ignore kind conditions
introduced for -Wconversion if -Wconversion-extra is present.
* invoke.texi: Add -Wconversion to -Wall; document new behaviour of
-Wconversion; document -Wconversion-extra.
gcc/testsuite/:
2010-05-19 Daniel Franke <franke.daniel@gmail.com>
PR fortran/44055
* gfortran.dg/c_sizeof_2.f90: Add -Wno-conversion to dg-options;
Fixed scope of C_SIZEOF.
* gfortran.dg/warn_conversion_2.f90: New.
From-SVN: r159586
---
gcc/fortran/ChangeLog | 13 +++++
gcc/fortran/gfortran.h | 1 +
gcc/fortran/intrinsic.c | 47 ++++++++++++++-----
gcc/fortran/invoke.texi | 13 +++--
gcc/fortran/lang.opt | 4 ++
gcc/fortran/options.c | 6 +++
gcc/testsuite/ChangeLog | 7 +++
gcc/testsuite/gfortran.dg/c_sizeof_2.f90 | 7 +--
.../gfortran.dg/warn_conversion_2.f90 | 6 +++
9 files changed, 86 insertions(+), 18 deletions(-)
create mode 100644 gcc/testsuite/gfortran.dg/warn_conversion_2.f90
diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 771a2639f25e..0d8fa4373481 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,16 @@
+2010-05-19 Daniel Franke <franke.daniel@gmail.com>
+
+ PR fortran/44055
+ * lang.opt (Wconversion-extra): New option.
+ * gfortran.h (gfc_option_t): Add warn_conversion_extra.
+ * options.c (gfc_init_options): Disable -Wconversion-extra by default.
+ (set_Wall): Enable -Wconversion.
+ (gfc_handle_option): Set warn_conversion_extra.
+ * intrinsic.c (gfc_convert_type_warn): Ignore kind conditions
+ introduced for -Wconversion if -Wconversion-extra is present.
+ * invoke.texi: Add -Wconversion to -Wall; document new behaviour of
+ -Wconversion; document -Wconversion-extra.
+
2010-05-19 Daniel Franke <franke.daniel@gmail.com>
PR fortran/42360
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index 903f05ca9d8a..15f2728f2285 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -2105,6 +2105,7 @@ typedef struct
int warn_aliasing;
int warn_ampersand;
int warn_conversion;
+ int warn_conversion_extra;
int warn_implicit_interface;
int warn_implicit_procedure;
int warn_line_truncation;
diff --git a/gcc/fortran/intrinsic.c b/gcc/fortran/intrinsic.c
index 02dea3039fd7..a92b5b54519e 100644
--- a/gcc/fortran/intrinsic.c
+++ b/gcc/fortran/intrinsic.c
@@ -4015,18 +4015,38 @@ gfc_convert_type_warn (gfc_expr *expr, gfc_typespec *ts, int eflag, int wflag)
/* At this point, a conversion is necessary. A warning may be needed. */
if ((gfc_option.warn_std & sym->standard) != 0)
- gfc_warning_now ("Extension: Conversion from %s to %s at %L",
- gfc_typename (&from_ts), gfc_typename (ts), &expr->where);
- else if (wflag && gfc_option.warn_conversion)
{
+ gfc_warning_now ("Extension: Conversion from %s to %s at %L",
+ gfc_typename (&from_ts), gfc_typename (ts),
+ &expr->where);
+ }
+ else if (wflag)
+ {
+ /* Two modes of warning:
+ - gfc_option.warn_conversion tries to be more intelligent
+ about the warnings raised and omits those where smaller
+ kinds are promoted to larger ones without change in the
+ value
+ - gfc_option.warn_conversion_extra does not take the kinds
+ into account and also warns for coversions like
+ REAL(4) -> REAL(8)
+
+ NOTE: Possible enhancement for warn_conversion
+ If converting from a smaller to a larger kind, check if the
+ value is constant and if yes, whether the value still fits
+ in the smaller kind. If yes, omit the warning.
+ */
+
/* If the types are the same (but not LOGICAL), and if from-kind
is larger than to-kind, this may indicate a loss of precision.
The same holds for conversions from REAL to COMPLEX. */
if (((from_ts.type == ts->type && from_ts.type != BT_LOGICAL)
- && from_ts.kind > ts->kind)
+ && ((gfc_option.warn_conversion && from_ts.kind > ts->kind)
+ || gfc_option.warn_conversion_extra))
|| ((from_ts.type == BT_REAL && ts->type == BT_COMPLEX)
- && from_ts.kind > ts->kind))
- gfc_warning_now ("Possible loss of precision in conversion "
+ && ((gfc_option.warn_conversion && from_ts.kind > ts->kind)
+ || gfc_option.warn_conversion_extra)))
+ gfc_warning_now ("Possible change of value in conversion "
"from %s to %s at %L", gfc_typename (&from_ts),
gfc_typename (ts), &expr->where);
@@ -4037,18 +4057,21 @@ gfc_convert_type_warn (gfc_expr *expr, gfc_typespec *ts, int eflag, int wflag)
an overflow error with range checking. */
else if (from_ts.type == BT_INTEGER
&& (ts->type == BT_REAL || ts->type == BT_COMPLEX)
- && from_ts.kind > ts->kind)
- gfc_warning_now ("Possible loss of digits in conversion "
+ && ((gfc_option.warn_conversion && from_ts.kind > ts->kind)
+ || gfc_option.warn_conversion_extra))
+ gfc_warning_now ("Possible change of value in conversion "
"from %s to %s at %L", gfc_typename (&from_ts),
gfc_typename (ts), &expr->where);
/* If REAL/COMPLEX is converted to INTEGER, or COMPLEX is converted
to REAL we almost certainly have a loss of digits, regardless of
the respective kinds. */
- else if (((from_ts.type == BT_REAL || from_ts.type == BT_COMPLEX)
- && ts->type == BT_INTEGER)
- || (from_ts.type == BT_COMPLEX && ts->type == BT_REAL))
- gfc_warning_now ("Likely loss of digits in conversion from"
+ else if ((((from_ts.type == BT_REAL || from_ts.type == BT_COMPLEX)
+ && ts->type == BT_INTEGER)
+ || (from_ts.type == BT_COMPLEX && ts->type == BT_REAL))
+ && (gfc_option.warn_conversion
+ || gfc_option.warn_conversion_extra))
+ gfc_warning_now ("Possible change of value in conversion from "
"%s to %s at %L", gfc_typename (&from_ts),
gfc_typename (ts), &expr->where);
}
diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi
index 7b3fa6d4baf5..1b14cef8db2f 100644
--- a/gcc/fortran/invoke.texi
+++ b/gcc/fortran/invoke.texi
@@ -688,8 +688,8 @@ warnings.
@cindex warnings, all
Enables commonly used warning options pertaining to usage that
we recommend avoiding and that we believe are easy to avoid.
-This currently includes @option{-Waliasing},
-@option{-Wampersand}, @option{-Wsurprising}, @option{-Wintrinsics-std},
+This currently includes @option{-Waliasing}, @option{-Wampersand},
+@option{-Wconversion}, @option{-Wsurprising}, @option{-Wintrinsics-std},
@option{-Wno-tabs}, @option{-Wintrinsic-shadow} and @option{-Wline-truncation}.
@item -Waliasing
@@ -746,7 +746,14 @@ Warn when a source code line will be truncated.
@opindex @code{Wconversion}
@cindex warnings, conversion
@cindex conversion
-Warn about implicit conversions between different types.
+Warn about implicit conversions that are likely to change the value of
+the expression after conversion. Implied by @option{-Wall}.
+
+@item -Wconversion-extra
+@opindex @code{Wconversion-extra}
+@cindex warnings, conversion
+@cindex conversion
+Warn about implicit conversions between different types and kinds.
@item -Wimplicit-interface
@opindex @code{Wimplicit-interface}
diff --git a/gcc/fortran/lang.opt b/gcc/fortran/lang.opt
index 1438aa2d0ca9..57ac4293351c 100644
--- a/gcc/fortran/lang.opt
+++ b/gcc/fortran/lang.opt
@@ -92,6 +92,10 @@ Wconversion
Fortran Warning
; Documented in C
+Wconversion-extra
+Fortran Warning
+Warn about most implicit conversions
+
Wimplicit-interface
Fortran Warning
Warn about calls with implicit interface
diff --git a/gcc/fortran/options.c b/gcc/fortran/options.c
index 6a5a3db6f3bd..320dc722b2c0 100644
--- a/gcc/fortran/options.c
+++ b/gcc/fortran/options.c
@@ -78,6 +78,7 @@ gfc_init_options (unsigned int argc, const char **argv)
gfc_option.warn_character_truncation = 0;
gfc_option.warn_array_temp = 0;
gfc_option.warn_conversion = 0;
+ gfc_option.warn_conversion_extra = 0;
gfc_option.warn_implicit_interface = 0;
gfc_option.warn_line_truncation = 0;
gfc_option.warn_surprising = 0;
@@ -402,6 +403,7 @@ set_Wall (int setting)
{
gfc_option.warn_aliasing = setting;
gfc_option.warn_ampersand = setting;
+ gfc_option.warn_conversion = setting;
gfc_option.warn_line_truncation = setting;
gfc_option.warn_surprising = setting;
gfc_option.warn_tabs = !setting;
@@ -568,6 +570,10 @@ gfc_handle_option (size_t scode, const char *arg, int value,
gfc_option.warn_conversion = value;
break;
+ case OPT_Wconversion_extra:
+ gfc_option.warn_conversion_extra = value;
+ break;
+
case OPT_Wimplicit_interface:
gfc_option.warn_implicit_interface = value;
break;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d68e7c6f34a5..84c0dd71d1b8 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2010-05-19 Daniel Franke <franke.daniel@gmail.com>
+
+ PR fortran/44055
+ * gfortran.dg/c_sizeof_2.f90: Add -Wno-conversion to dg-options;
+ Fixed scope of C_SIZEOF.
+ * gfortran.dg/warn_conversion_2.f90: New.
+
2010-05-19 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
* lib/target-supports.exp (check_effective_target_sse2): New proc.
diff --git a/gcc/testsuite/gfortran.dg/c_sizeof_2.f90 b/gcc/testsuite/gfortran.dg/c_sizeof_2.f90
index 6e32cb34687e..fb65adce5f0e 100644
--- a/gcc/testsuite/gfortran.dg/c_sizeof_2.f90
+++ b/gcc/testsuite/gfortran.dg/c_sizeof_2.f90
@@ -1,8 +1,9 @@
! { dg-do compile }
-! { dg-options "-std=f2003 -Wall" }
+! { dg-options "-std=f2003 -Wall -Wno-conversion" }
! Support F2008's c_sizeof()
!
-integer(4) :: i
-i = c_sizeof(i) ! { dg-warning "Fortran 2008" }
+USE ISO_C_BINDING
+integer(C_SIZE_T) :: i
+i = c_sizeof(i) ! { dg-warning "Fortran 2008" }
end
diff --git a/gcc/testsuite/gfortran.dg/warn_conversion_2.f90 b/gcc/testsuite/gfortran.dg/warn_conversion_2.f90
new file mode 100644
index 000000000000..cb3b760a5e2b
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/warn_conversion_2.f90
@@ -0,0 +1,6 @@
+! { dg-do "compile" }
+! { dg-options "-Wconversion-extra" }
+
+ real(8) :: sqrt2
+ sqrt2 = sqrt(2.0) ! { dg-warning "conversion" }
+end
--
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