re PR fortran/61234 (Warn for use-stmt without explicit only-list.)

2014-08-22  Joost VandeVondele  <Joost.VandeVondele@mat.ethz.ch>
 
 	* gfortran.dg/use_without_only_1.f90: New test.
 
 2014-08-22  Joost VandeVondele  <Joost.VandeVondele@mat.ethz.ch>
 
 	PR fortran/61234
 	* lang.opt (Wuse-without-only): New flag.
 	* gfortran.h (gfc_option_t): Add it.
 	* invoke.texi: Document it.
 	* module.c (gfc_use_module): Warn if needed.
 	* options.c (gfc_init_options,gfc_handle_option): Init accordingly.

From-SVN: r214311

gcc/fortran/ChangeLog

@@ -1,3 +1,12 @@
+2014-08-22  Joost VandeVondele  <Joost.VandeVondele@mat.ethz.ch>
+
+	PR fortran/61234
+	* lang.opt (Wuse-without-only): New flag.
+	* gfortran.h (gfc_option_t): Add it.
+	* invoke.texi: Document it.
+	* module.c (gfc_use_module): Warn if needed.
+	* options.c (gfc_init_options,gfc_handle_option): Init accordingly.
+
 2014-08-21  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/62214

gcc/fortran/gfortran.h

@@ -2450,6 +2450,7 @@ typedef struct
   int warn_tabs;
   int warn_underflow;
   int warn_intrinsic_shadow;
+  int warn_use_without_only;
   int warn_intrinsics_std;
   int warn_character_truncation;
   int warn_array_temp;

gcc/fortran/invoke.texi

@@ -142,7 +142,7 @@ and warnings}.
 @gccoptlist{-Waliasing -Wall -Wampersand -Warray-bounds
 -Wc-binding-type -Wcharacter-truncation @gol
 -Wconversion -Wfunction-elimination -Wimplicit-interface @gol
--Wimplicit-procedure -Wintrinsic-shadow -Wintrinsics-std @gol
+-Wimplicit-procedure -Wintrinsic-shadow -Wuse-without-only -Wintrinsics-std @gol
 -Wline-truncation -Wno-align-commons -Wno-tabs -Wreal-q-constant @gol
 -Wsurprising -Wunderflow -Wunused-parameter -Wrealloc-lhs -Wrealloc-lhs-all @gol
 -Wtarget-lifetime -fmax-errors=@var{n} -fsyntax-only -pedantic -pedantic-errors
@@ -896,6 +896,13 @@ intrinsic; in this case, an explicit interface or @code{EXTERNAL} or
 @code{INTRINSIC} declaration might be needed to get calls later resolved to
 the desired intrinsic/procedure.  This option is implied by @option{-Wall}.
 
+@item -Wuse-without-only
+@opindex @code{Wuse-without-only}
+@cindex warnings, use statements
+@cindex intrinsic
+Warn if a @code{USE} statement has no @code{ONLY} qualifier and 
+thus implicitly imports all public entities of the used module.
+
 @item -Wunused-dummy-argument
 @opindex @code{Wunused-dummy-argument}
 @cindex warnings, unused dummy argument

gcc/fortran/lang.opt

@@ -257,6 +257,10 @@ Wintrinsics-std
 Fortran Warning
 Warn on intrinsics not part of the selected standard
 
+Wuse-without-only
+Fortran Warning
+Warn about USE statements that have no ONLY qualifier
+
 Wopenmp-simd
 Fortran
 ; Documented in C

gcc/fortran/module.c

@@ -6741,6 +6741,9 @@ gfc_use_module (gfc_use_list *module)
   only_flag = module->only_flag;
   current_intmod = INTMOD_NONE;
 
+  if (!only_flag && gfc_option.warn_use_without_only) 
+    gfc_warning_now ("USE statement at %C has no ONLY qualifier");
+
   filename = XALLOCAVEC (char, strlen (module_name) + strlen (MODULE_EXTENSION)
 			       + 1);
   strcpy (filename, module_name);

gcc/fortran/options.c

@@ -107,6 +107,7 @@ gfc_init_options (unsigned int decoded_options_count,
   gfc_option.warn_tabs = 1;
   gfc_option.warn_underflow = 1;
   gfc_option.warn_intrinsic_shadow = 0;
+  gfc_option.warn_use_without_only = 0;
   gfc_option.warn_intrinsics_std = 0;
   gfc_option.warn_align_commons = 1;
   gfc_option.warn_real_q_constant = 0;
@@ -728,6 +729,10 @@ gfc_handle_option (size_t scode, const char *arg, int value,
       gfc_option.warn_intrinsic_shadow = value;
       break;
 
+    case OPT_Wuse_without_only:
+      gfc_option.warn_use_without_only = value;
+      break;
+
     case OPT_Walign_commons:
       gfc_option.warn_align_commons = value;
       break;

gcc/testsuite/ChangeLog

@@ -1,3 +1,7 @@
+2014-08-22  Joost VandeVondele  <Joost.VandeVondele@mat.ethz.ch>
+
+	* gfortran.dg/use_without_only_1.f90: New test.
+
 2014-08-22  Igor Zamyatin  <igor.zamyatin@intel.com>
 
 	PR other/62008
@@ -5,7 +9,7 @@
 
 2014-08-22  Tony Wang  <tony.wang@arm.com>
 
-        * g++.dg/tls/thread_local6.C: Skip this test case when target uses
+	* g++.dg/tls/thread_local6.C: Skip this test case when target uses
 	dejagnu wrapper.
 
 2014-08-21  Thomas Koenig  <tkoenig@gcc.gnu.org>

gcc/testsuite/gfortran.dg/use_without_only_1.f90

@@ -0,0 +1,22 @@
+! PR fortran/61234 Warn for use-stmt without explicit only-list.
+! { dg-do compile }
+! { dg-options "-Wuse-without-only" }
+MODULE foo
+  INTEGER :: bar
+END MODULE
+
+MODULE testmod
+  USE foo ! { dg-warning "has no ONLY qualifier" }
+  IMPLICIT NONE
+CONTAINS
+  SUBROUTINE S1
+     USE foo ! { dg-warning "has no ONLY qualifier" }
+  END SUBROUTINE S1
+  SUBROUTINE S2
+     USE foo, ONLY: bar 
+  END SUBROUTINE
+  SUBROUTINE S3
+     USE ISO_C_BINDING ! { dg-warning "has no ONLY qualifier" }
+  END SUBROUTINE S3
+END MODULE
+! { dg-final { cleanup-modules "foo testmod" } }