===================================================================
@@ -3081,6 +3081,44 @@
end if;
end if;
+ -- Check suspicious use of Import in pure unit
+
+ if Is_Imported (E) and then Is_Pure (Cunit_Entity (Current_Sem_Unit))
+
+ -- Ignore internally generated entity. This happens in some cases
+ -- of subprograms in specs, where we generate an implied body.
+
+ and then Comes_From_Source (Import_Pragma (E))
+
+ -- Assume run-time knows what it is doing
+
+ and then not GNAT_Mode
+
+ -- Assume explicit Pure_Function means import is pure
+
+ and then not Has_Pragma_Pure_Function (E)
+
+ -- Don't need warning in relaxed semantics mode
+
+ and then not Relaxed_RM_Semantics
+
+ -- Assume convention Intrinsic is OK, since this is specialized.
+ -- This deals with the DEC unit current_exception.ads
+
+ and then Convention (E) /= Convention_Intrinsic
+
+ -- Assume that ASM interface knows what it is doing. This deals
+ -- with unsigned.ads in the AAMP back end.
+
+ and then Convention (E) /= Convention_Assembler
+ then
+ Error_Msg_N
+ ("pragma Import in Pure unit??", Import_Pragma (E));
+ Error_Msg_NE
+ ("\calls to & may be omitted (RM 10.2.1(18/3))??",
+ Import_Pragma (E), E);
+ end if;
+
return True;
end Freeze_Profile;
The warning for use of Import in a Pure unit is refined so that it is omitted if an explicit Pure_Function aspect is given, as shown by the following test, compiled with -gnatl 1. package PureImportF is 2. pragma Pure (PureImportF); 3. function F (A : integer) return integer; 4. pragma Import (C, F); | >>> warning: pragma Import in Pure unit >>> warning: calls to "F" may be omitted (RM 10.2.1(18/3)) 5. function F2 (A : integer) return integer; 6. pragma Pure_Function (F2); 7. pragma Import (C, F2); 8. end PureImportF; Tested on x86_64-pc-linux-gnu, committed on trunk 2015-01-30 Robert Dewar <dewar@adacore.com> * freeze.adb (Freeze_Profile): Add test for suspicious import in pure unit. * sem_prag.adb (Process_Import_Or_Interface): Test for suspicious use in Pure unit is now moved to Freeze (to properly catch Pure_Function exemption).