From: Marc Poulhiès Date: Thu, 30 Jun 2022 11:35:10 +0000 (+0200) Subject: [Ada] Fix if expression returning slice X-Git-Tag: basepoints/gcc-14~5548 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7a03001cd2dadbe845f109382e4c0dc2dbb50820;p=thirdparty%2Fgcc.git [Ada] Fix if expression returning slice The compiler incorrectly assumed the prefix for a slice returned in one branch of an if expression has its bounds known at compile time and would crash when this is not true. gcc/ada/ * exp_ch4.adb (Expand_N_If_Expression): Test for compile time known bounds when handling slices. --- diff --git a/gcc/ada/exp_ch4.adb b/gcc/ada/exp_ch4.adb index 911bdf31b78..18fb88f3f9f 100644 --- a/gcc/ada/exp_ch4.adb +++ b/gcc/ada/exp_ch4.adb @@ -6174,7 +6174,13 @@ package body Exp_Ch4 is Slice_Bnd : Node_Id) return Node_Id is begin - if Nkind (Elsex) = N_Slice then + -- We need to use the special processing for slices only if + -- they do not have compile-time known bounds; if they do, they + -- can be treated like any other expressions. + + if Nkind (Elsex) = N_Slice + and then not Compile_Time_Known_Bounds (Etype (Elsex)) + then if Compile_Time_Known_Value (Slice_Bnd) and then Expr_Value (Slice_Bnd) = Then_Bnd then @@ -6230,7 +6236,11 @@ package body Exp_Ch4 is begin Get_First_Index_Bounds (Etype (Thenx), Then_Lo, Then_Hi); - if Nkind (Elsex) = N_Slice then + -- See the rationale in Build_New_Bound + + if Nkind (Elsex) = N_Slice + and then not Compile_Time_Known_Bounds (Etype (Elsex)) + then Slice_Lo := Low_Bound (Discrete_Range (Elsex)); Slice_Hi := High_Bound (Discrete_Range (Elsex)); Get_First_Index_Bounds @@ -6289,7 +6299,11 @@ package body Exp_Ch4 is Set_Suppress_Assignment_Checks (Last (Then_List)); - if Nkind (Elsex) = N_Slice then + -- See the rationale in Build_New_Bound + + if Nkind (Elsex) = N_Slice + and then not Compile_Time_Known_Bounds (Etype (Elsex)) + then Else_List := New_List ( Make_Assignment_Statement (Loc, Name =>