I wanted to compile an Ada package I am writing as a student at the University of Stuttgart, Germany.
The following happened: $ gnatmake -gnaty3acefhiklmnrpt permutations.adb gcc -c -gnaty3acefhiklmnrpt permutations.adb +===========================GNAT BUG DETECTED==============================+ | 3.3 20040913 (GNAT for Mac OS X build 1650) (powerpc-unknown-darwin) | | Assert_Failure sinfo.adb:1593 | | Error detected at permutations.adb:68:7 | | Please submit a bug report; see http://gcc.gnu.org/bugs.html. | | Include the entire contents of this bug box in the report. | | Include the exact gcc or gnatmake command that you entered. | | Also include sources listed below in gnatchop format | | concatenated together with no headers between files. | +==========================================================================+ Please include these source files with error report permutations.adb permutations.ads list may be incomplete permutations.adb:80:23: (style) space required compilation abandoned gnatmake: "permutations.adb" compilation error The source files: permutations.adb: -- FILE: permutations.adb -- -- PROJECT: Programmieruebungen, Uebungsblatt 02 -- VERSION: 1.0 -- DATE: 08 Nov 2006 -- AUTHOR: Fritjof A. Mayer -- ------------------------------------------------------------------------------ -- -- PACKAGE BODY Permutations -- package body Permutations is -- FUNCTION Next_Perm -- -- Originally written on 10 Nov 2005 -- Blatt 2, Aufgabe 3, Programmierkurs I, WS05/06 -- by Fritjof A. Mayer -- -- Generates next permutation. -- Algorithm taken from "Einfuehrung in die Informatik I WS05/06" function Next_Perm (Perm : Permutation) return Permutation is Next_P : Permutation (Perm'Range) := Perm; I, J, K, Smallest, Trans : Natural; N : constant Natural := Perm'Last; begin -- search backwards for P (I) < P (I + 1) -- starting at I = N - 1 I := N - 1; while I >= 1 and Perm (I) > Perm (I + 1) loop I := I - 1; end loop; -- search forwards for smallest Z > P (I), Z = P (J) -- starting at J = I + 1 Smallest := I + 1; for J in (I + 1) .. N loop if Perm (J) < Perm (Smallest) and Perm (J) > Perm (I) then Smallest := J; end if; end loop; J := Smallest; -- swap P (I) and P (J) in next permutation Next_P (I) := Perm (J); Next_P (J) := Perm (I); -- sort elements P (I + 1) .. P (N) -- by inverting their sequence K := 0; while (I + 1) + K < N - K loop Trans := Next_P ((I + 1) + K); Next_P ((I + 1) + K) := Next_P (N - K); Next_P (N - K) := Trans; K := K + 1; end loop; return Next_P; end Next_Perm; -- FUNCTION Word_Perm -- -- Generates all permutations of a word, first and last -- character are not permuted -- -- Example: ... -- function Word_Perm (Word : String) return P_Words is All_Perms : P_Words (1 .. (Word'Length - 2)**2, Word'Length); Perm : Permutation (1 .. Word'Length - 2); begin for I in Perm'Range loop Perm (I) := I; end loop; for I in All_Perms'Range loop All_Perms (I, 1) := Word (Word'First); for J in Perm'Range loop All_Perms (I, J) := Word (Perm (J)); end loop; All_Perms (I,Word'Length) := Word (Word'Last); Perm := Next_Perm (Perm); end loop; return All_Perms; end Word_Perm; end Permutations; permutations.ads: package Permutations is type Permutation is array (Positive range <>) of Positive; type P_Words is array (Positive range <>, Positive range <>) of Character; function Next_Perm (Perm : Permutation) return Permutation; end Permutations; ---------------------------------------------------------------- ---------------------------------------------------------------- I think the problem is here: ... function Word_Perm (Word : String) return P_Words is All_Perms : P_Words (1 .. (Word'Length - 2)**2, Word'Length); Perm : Permutation (1 .. Word'Length - 2); begin ... P_Words needs index constraints, those are ranges. 1 .. (Word'Length - 2)**2 is a range Word'Length is just a number and no range. Normally i should receive an error message: invalid index constraint When I change this to All_Perms : P_Words (1 .. (Word'Length - 2)**2, 1 .. Word'Length); it compiles without errors. -- Summary: invalid index constraint causes GNAT to crash Product: gcc Version: 3.3 Status: UNCONFIRMED Severity: normal Priority: P3 Component: ada AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: mayerff at studi dot informatik dot uni-stuttgart dot de http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29762
