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If you have been folllowing the thread posted by Tim Wisseman, he reported a problem with the compiler producing erroneous addresses for Global variables which would GPF (or lock up) his program.
I have come accross the exact same problem I believe. It is hard to make a sample test program since I have over 5000 lines of code and to reproduce the error is very difficult.
I think this is a very serious error in the compiler and deserves PBs "full attention" to solve it. Here is what I have experienced so far and I'll try to document it as best as possible:
My program works fine. I add a few lines of code and then all of a sudden the program is locking up at a section of code that was written a long time ago and works perfectly. In doing some testing here is what I noticed:
Here is a major procedure in my program which process a bunch of messages sent to this routine:
The problem is this:
My Procedure has a very complex Select Case structure (and lots of If Blocks). Near the end of the Select case structure (noted in code) if I add another sub call (even if it is a dummy with no code in it), I then have problems with a sub call near the top quarter of the Select case structure.
The NewForm sub call does get executed but when some code in it accesses a:
Global Array
The program now locks up. I used the msgbox command in different places until I found where the program locked up. I was able to even have the program lick up when I used the varptr command with that global array.
Here is what I think is happening.
In certain circumstances when there are many procedure calls and the Select case/If Then blocks get nested a bit deep, the compiler somehow "loses" some tracking information about some Global variables, so when some code later in the program uses those variables, the compiler puts erronneous addresses for the variables and memory is probably overwritten.
I know "absolutely" this is a BUG in the Compiler, since if I simply add a single line of code (which is a call to a dummy procedure that does nothing), then the program locks up at a previously written section that has worked flawlessly. When I remove the single line of code, then everything works just fine.
There is absolutely NO way that adding a single line of code that is a sub call to a dummy procedure (no code in the sub), can cause a bug in my software. This is impossible !
I am still not sure "exactly" the mechanism of the problem yet, since it will not likely show up on a small sized program that has less structure in it. This makes it hard to document expect in a very large program (which some programmers cannot give out the code).
I have come accross the exact same problem I believe. It is hard to make a sample test program since I have over 5000 lines of code and to reproduce the error is very difficult.
I think this is a very serious error in the compiler and deserves PBs "full attention" to solve it. Here is what I have experienced so far and I'll try to document it as best as possible:
My program works fine. I add a few lines of code and then all of a sudden the program is locking up at a section of code that was written a long time ago and works perfectly. In doing some testing here is what I noticed:
Here is a major procedure in my program which process a bunch of messages sent to this routine:
Code:
' --------------------------------------------------------------------------------
Sub EZ_Events(FormName$, CID&, CMsg&, CVal&, Cancel&) EXPORT
Local TMP$, I&, hCtrl&, WS&, EX&, MyColor&
Local D$, X&, N&, P1&, P2&
Select case FormName$
case "PARENT" ' or any Form Name you choose
Select case CID&
case %EZ_Window ' This is a Window message
if CMsg&=%EZ_Close then
CheckSave
EZ_UnloadForm "TopTool"
end if
if CMsg&=%EZ_FreeNow then
EZ_RedrawForm "" ' redraws desktop
end if
case 230
if CMsg&=%EZ_Change then
BringForward
end if
case 901,101 ' New Form
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "New Form"
else
' ------------------------------------------------
' The lock up occurs during the following sub call
NewForm
' -------------------------------------------------
end if
case 902,102 ' Open Form
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Open Form"
else
OpenForm
end if
case 903,103 ' Save Form
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Save Form"
else
if MainFlag& then SaveForm 0
end if
case 904,104 ' Save Form As
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Save Form As"
else
if MainFlag& then SaveForm 1
end if
case 905,105 ' close form
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Close Form"
else
if MainFlag& then
X&=CloseMainForm()
end if
end if
case 906 ' exit program
EZ_UnloadForm "Parent"
case 911, 106 ' Edit Form
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Edit Form"
else
DisplayFormProps
end if
case 107 ' Edit Menu
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Drag Form from Inside"
else
if App_CanDrag& then
App_CanDrag&=0
else
App_CanDrag&=1
end if
end if
case 941, 110
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Edit Mode"
else
SetEditMode 1
end if
case 942,111
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Test Mode"
else
SetEditMode 0
end if
case 943,112
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Reset Tab Order"
else
SetZorder 0
end if
case 931, 108
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Add Toolbar"
else
if App_EditMode& then MakeControl 50
end if
case 932,109
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Edit Toolbar"
else
if App_EditMode& then DisplayToolbarProps
end if
case 961,113
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Generate Form Code"
else
DisplayGenProps
end if
case 962,114
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Generate Project Code"
else
end if
case 115
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Move the Next Control you Select to 0,0"
else
if App_CenterFlag&=0 then
App_CenterFlag&=-1
else
App_CenterFlag&=0
end if
end if
case 913 to 918
X&=CID&-913
N&=X&
if X&=3 then N&=4
if X&=4 then N&=8
if X&=5 then N&=16
EZ_SetFGrid N&
D$="Character Size"
for I&=0 to 5
if I&=X& then TMP$="X" else TMP$=""
if I&=1 then D$="1 X 1"
if I&=2 then D$="2 X 2"
if I&=3 then D$="4 X 4"
if I&=4 then D$="8 X 8"
if I&=5 then D$="16 X 16"
EZ_SetMenuItem SMenu1B&, 913+I&, D$ , TMP$
next I&
case 951 to 956
X&=CID&-950
if X&>2 then
N&=(X&-2)*4
else
N&=X&
end if
EZ_SetGrid N&, N&
for I&=1 to 6
if I&>2 then
N&=(I&-2)*4
else
N&=I&
end if
if I&=X& then TMP$="X" else TMP$=""
D$=ltrim$(str$(N&))
EZ_SetMenuItem SMenu5&, 950+I&,D$+" X "+D$ , TMP$
next I&
case 971 to 973
SetDFont CID&-971
case 981 to 997
if App_EditMode& then
MakeControl CID&-980
end if
case else
end select
case "MAIN"
Select case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
if App_CheckSave& then CheckSave
EZ_UnloadForm "FLOAT1"
end if
if CMsg&=%EZ_FreeNow then
for X&=0 to ubound(App_Menus)
if App_Menus(X&)<>0 then
EZ_DelMenu App_Menus(X&)
end if
next X&
end if
if CMsg&=%EZ_Focus then
EZ_SetText "Parent", 200, "%EZ_Window"
EZ_SetText "Parent", 201, "%EZ_Focus"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
if CMsg&=%EZ_NoFocus then
EZ_SetText "Parent", 200, "%EZ_Window"
EZ_SetText "Parent", 201, "%EZ_NoFocus"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
if CMsg&=%EZ_Change then
EZ_SetText "Parent", 200, "%EZ_Window"
EZ_SetText "Parent", 201, "%EZ_Change"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
if CMsg&=%EZ_LButtonDown then
EZ_SetText "Parent", 200, "%EZ_Window"
EZ_SetText "Parent", 201, "%EZ_LButtonDown"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
if App_CanDrag&<>0 then
EZ_DragForm "Main"
end if
end if
if CMsg&=%EZ_LButtonDC then
if App_EditMode&=1 then
DisplayFormProps
else
EZ_SetText "Parent", 200, "%EZ_Window"
EZ_SetText "Parent", 201, "%EZ_LButtonDC"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
end if
if CMsg&=%EZ_RButtonUp then
EZ_SetText "Parent", 200, "%EZ_Window"
EZ_SetText "Parent", 201, "%EZ_RButtonUp"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
case 50 to 99
' toolbar messages
Select case CMsg&
case %EZ_Click
D$="%EZ_Click"
EZ_SetText "Parent", 200, "Toolbar Button"+str$(CID&-50)
EZ_SetText "Parent", 201, D$
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
case %EZ_ToolTip
D$="%EZ_ToolTip"
EZ_SetToolTip "Button"+str$(CID&-50)
case else
D$=""
End Select
case 100 to 400
if CMsg&=%EZ_LButtonDC then
DisplayProps CID&
elseif CMsg&=%EZ_RButtonUp then
AlignDialog CID&
else
Select case CMsg&
case %EZ_Click
D$="%EZ_Click"
case %EZ_DClick
D$="%EZ_DClick"
case %EZ_Focus
D$="%EZ_Focus"
case %EZ_NoFocus
D$="%EZ_NoFocus"
case %EZ_Disable
D$="%EZ_Disable"
case %EZ_Change
D$="%EZ_Change"
case %EZ_Timer
D$="%EZ_Timer"
case %EZ_ToolTip
D$="%EZ_ToolTip"
case %EZ_LButtonDown
D$="%EZ_LButtonDown"
case %EZ_FreeNow
D$="%EZ_FreeNow"
case %EZ_SubClass
D$="" ' this message will be continuous
case else
D$=""
End Select
if D$<>"" then
EZ_SetText "Parent", 200, App_CName$(CID&-99)
EZ_SetText "Parent", 201, D$
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
end if
if CMsg&=%EZ_Drag then
end if
if CMsg&=%EZ_Drop then
end if
case >=500 ' menus
N&=(CID&-495)/5
if N&<=%App_Max_Menu then
D$=ltrim$(rtrim$(App_F.FMenuItems(N&)))
if left$(D$,3)="..." then D$=mid$(D$,4)
D$=remove$(D$,"&")
EZ_SetText "Parent", 200, "M: "+D$
EZ_SetText "Parent", 201, "N/A"
EZ_SetText "Parent", 202, ltrim$(str$(CVal&))
end if
case else
end select
case "FLOAT1"
Select case CID&
case 101 to 117
if CMsg&=%EZ_Click then MakeControl CID&-100
if CMsg&=%EZ_ToolTip then MakeToolTips CID&-100
case 118
if CMsg&=%EZ_Click then MakeControl 49
if CMsg&=%EZ_ToolTip then MakeToolTips 49
case 200
if CMsg&=%EZ_Change then
App_ActiveLayer&=val(mid$(EZ_GetText("FLOAT1", 200), 7))
EZ_DisplayLayer "Main", App_ActiveLayer&, 0
end if
case 300
if CMsg&=%EZ_Click then
DoToolBar
end if
if CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Hide Visual Designer"
end if
case else
end select
case "PROPS"
Select case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
EZ_ShowForm "Float1"
EZ_Enable "Main"
end if
case 103
if CMsg&=%EZ_Click then BrowseBitmaps
case 104
if CMsg&=%EZ_Click then BrowseIcons
case 108
if CMsg&=%EZ_Change then
Select Case rtrim$(EZ_GetText("Props", 108))
case "Custom Bitmap"
BrowseBitmaps
EZ_SelectItem "Props", 107,1
case else
D$=ltrim$(rtrim$(EZ_GetText("Props", 108)))
EZ_SetText "Props", 102, D$
if left$(D$,6)="%Large" then
EZ_SelectItem "Props", 107,1
else
EZ_SelectItem "Props", 107,0
end if
End Select
end if
case 109
if CMsg&=%EZ_Change then
Select Case rtrim$(EZ_GetText("Props", 109))
case "Custom Icon"
BrowseIcons
case else
D$=ltrim$(rtrim$(EZ_GetText("Props", 109)))
EZ_SetText "Props", 102, D$
End Select
end if
case 120, 121
if CMsg&=%EZ_Click then
if CID&=120 then
TMP$="Foreground"
ColorPickVal&=App_C(0).CFGColor
ColorType&=1
else
TMP$="Background"
ColorPickVal&=App_C(0).CBGColor
ColorType&=2
end if
TMP$="Select "+TMP$+" Color"
EZ_Form "ColorPick", "Props", TMP$,0,0, 24,24, "CRMN"
if CID&=120 then
' App_C(0).CFGColor=ColorPickVal&
else
' App_C(0).CBGColor=ColorPickVal&
end if
end if
case 122
if CMsg&=%EZ_Click then
if rtrim$(App_C(0).CFontName)<>"" then
EZ_DefFont -1, rtrim$(App_C(0).CFontName), App_C(0).CFontPitch, rtrim$(App_C(0).CFontProp)
else
if App_DefaultFName$<>"" then
EZ_DefFont -1, App_DefaultFName$, App_DefaultFSize&, App_DefaultFProp$
else
EZ_DefFont -1, "System", 10, "BV"
end if
end if
if EZ_ChooseFont( "Props", MyColor&, "") then
SetCFont 1
else
SetCFont 0
end if
end if
case 199 ' Delete
if EZ_MsgBox("Props", "{S}Are you sure you want to delete this Control ?", "Delete Control", "YN") then
EZ_UnloadForm "Props"
DeleteControl App_PNum&
App_PNum&=0
UpdateCombo
end if
case 200 ' cancel
EZ_UnloadForm "Props"
App_PNum&=0
case 201 ' Apply
SetData App_PNum&
EZ_UnloadForm "Props"
RedoControl App_PNum&
App_PNum&=0
SetZorder 0
UpdateCombo
EZ_DisplayLayer "Main", App_ActiveLayer&, 0
case else
End Select
case "FORMPROPS"
Select case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
EZ_ShowForm "Float1"
EZ_Enable "Main"
end if
case 121
if CMsg&=%EZ_Click then
TMP$="Background"
ColorType&=2
TMP$="Select "+TMP$+" Color"
EZ_Form "ColorPick2", "FormProps", TMP$,0,0, 24,24, "CRMN"
end if
case 200 ' cancel
EZ_UnloadForm "FormProps"
case 201 ' Apply
UpdateControls
TMP$=rtrim$(EZ_GetText("FormProps", 100))
TMP$=remove$(TMP$, ANY " |[email protected]#$%^&*()-+={}[]\:;'<>,.?/")
TMP$=remove$(TMP$, chr$(34))
if TMP$="" then
TMP$="Form1"
end if
App_F.FName=TMP$
App_F.FTitle=rtrim$(EZ_GetText("FormProps",101))
App_F.FColor=ColorPickVal&
App_F.FProps=GetFormProps()
App_F.FMenu&=EZ_GetCheck("FormProps", 120)
TMP$=EZ_GetText("FormProps", 130)
for N&=1 to %App_Max_Menu
App_F.FMenuItems(N&)=""
next N&
N&=0
do
P1&=instr(TMP$, chr$(13)+chr$(10))
if P1&<>0 then
D$=left$(TMP$, P1&-1)
TMP$=mid$(TMP$, P1&+2)
else
P2&=instr(TMP$, chr$(13))
if P2&<>0 then
D$=left$(TMP$, P1&-1)
TMP$=mid$(TMP$, P1&+1)
else
D$=TMP$
TMP$=""
if D$="" then exit do
end if
end if
if D$<>"" then
N&=N&+1
if N&>%App_Max_Menu then exit do
App_F.FMenuItems(N&)=D$
end if
loop
EZ_UnloadForm "FormProps"
App_CheckSave&=0
EZ_UnloadForm "Main"
BuildForm
UpdateCombo
App_CheckSave&=1
case else
End Select
case "COLORPICK"
Select case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
DisplaySample 1
end if
case 100 to 131
ColorPickVal&=CID&-100
ActiveColor 1
EZ_SetFocus "ColorPick", 201
if ColorType&=1 then
App_C(0).CFGColor=ColorPickVal&
if App_C(0).CBGColor=-1 then App_C(0).CBGColor=15
else
App_C(0).CBGColor=ColorPickVal&
if App_C(0).CFGColor=-1 then App_C(0).CFGColor=0
end if
case 200
App_C(0).CFGColor=-1
App_C(0).CBGColor=-1
EZ_UnloadForm "ColorPick"
case 201
EZ_UnloadForm "ColorPick"
End Select
case "COLORPICK2"
Select case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
EZ_UnloadControl "FormProps", 150
EZ_SetForm "FormProps", 0
if ColorPickVal&>=0 then
EZ_Color 0, ColorPickVal&
else
EZ_Color -1,-1
end if
EZ_Label 150, 1,16.5,16,5, "", "F"
EZ_Color -1,-1
end if
case 100 to 131
ColorPickVal&=CID&-100
ColorType&=3
ActiveColor 1
EZ_SetFocus "ColorPick2", 201
case 200
ColorPickVal&=-1
EZ_UnloadForm "ColorPick2"
case 201
EZ_UnloadForm "ColorPick2"
End Select
case "TOPTOOL"
Select Case CID&
case %EZ_Window
case 101 to 107
if CMsg&=%EZ_Click then
X&=CID&-100
Select case X&
case 1
D$=App_CodeDeclare$(1)
TMP$="Constants in Clipboard !"
case 2
D$=App_CodeGlobal$(1)
TMP$="Globals in Clipboard !"
case 3
D$=App_CodeMain$(1)
TMP$="EZ_Form in Clipboard !"
case 4
D$=App_CodeDesign$(1)
TMP$="Controls in Clipboard !"
case 5
D$=App_CodeEvent$(1)
TMP$="Events in Clipboard !"
case 6
D$=App_CodeSubs$(1)
TMP$="Subs in Clipboard !"
case 7
D$=App_CodeSkeleton$(1)
TMP$="Skeleton in Clipboard !"
case else
D$=""
End Select
if D$<>"" then
EZ_SetClipboard D$
EZ_SetText "TopTool", 200, TMP$
else
EZ_SetClipboard ""
EZ_SetText "TopTool", 200, "NO Code Generated !"
end if
elseif CMsg&=%EZ_ToolTip then
X&=CID&-100
Select case X&
case 1
D$="Constants"
case 2
D$="Globals"
case 3
D$="Form"
case 4
D$="Controls"
case 5
D$="Events"
case 6
D$="Subroutines"
case 7
D$="Skeleton"
case else
D$=""
End Select
EZ_SetToolTip D$
end if
case 108
if CMsg&=%EZ_Click then
EZ_HideForm "TopTool"
EZ_ShowForm "Parent"
EZ_ShowPopUps "Parent"
elseif CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Return to Visual Designer"
end if
case 109
if CMsg&=%EZ_Click then
EZ_MinimizeForm "TopTool"
elseif CMsg&=%EZ_ToolTip then
EZ_SetToolTip "Minimize Toolbar"
end if
case else
End Select
case "GENPROPS"
Select Case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
EZ_ShowForm "Float1"
EZ_Enable "Main"
end if
case 200
if CMsg&=%EZ_Click then EZ_SetSelect "GenProps", 100, -1, 1
case 210
if CMsg&=%EZ_Click then EZ_SetSelect "GenProps", 100, -1, 0
case 400 ' Generate
if CMsg&=%EZ_Click then
FlagControls 0
GenCode 1, 1
EZ_UnloadForm "GenProps"
DoToolBar
end if
case 410 ' Cancel
if CMsg&=%EZ_Click then
EZ_UnloadForm "GenProps"
end if
case else
End Select
case "ALIGNDLG"
Select Case CID&
case %EZ_Window
if CMsg&=%EZ_Close then
EZ_ShowForm "Float1"
EZ_Enable "Main"
end if
case 1
if CMsg&=%EZ_Click then
' ------------------------------------------------
' If I add the following sub call it causes the above
' sub call (NewForm) to lock up:
' DoDummyProc
' but if I don't use the call everything is OK
EZ_UnloadForm "AlignDlg"
' ------------------------------------------------
end if
case 2
if CMsg&=%EZ_Click then
EZ_UnloadForm "AlignDlg"
end if
case 200
if CMsg&=%EZ_Click then EZ_SetSelect "AlignDlg", 100, -1, 1
case 210
if CMsg&=%EZ_Click then EZ_SetSelect "AlignDlg", 100, -1, 0
case else
End Select
case else
End Select
End Sub
My Procedure has a very complex Select Case structure (and lots of If Blocks). Near the end of the Select case structure (noted in code) if I add another sub call (even if it is a dummy with no code in it), I then have problems with a sub call near the top quarter of the Select case structure.
The NewForm sub call does get executed but when some code in it accesses a:
Global Array
The program now locks up. I used the msgbox command in different places until I found where the program locked up. I was able to even have the program lick up when I used the varptr command with that global array.
Here is what I think is happening.
In certain circumstances when there are many procedure calls and the Select case/If Then blocks get nested a bit deep, the compiler somehow "loses" some tracking information about some Global variables, so when some code later in the program uses those variables, the compiler puts erronneous addresses for the variables and memory is probably overwritten.
I know "absolutely" this is a BUG in the Compiler, since if I simply add a single line of code (which is a call to a dummy procedure that does nothing), then the program locks up at a previously written section that has worked flawlessly. When I remove the single line of code, then everything works just fine.
There is absolutely NO way that adding a single line of code that is a sub call to a dummy procedure (no code in the sub), can cause a bug in my software. This is impossible !
I am still not sure "exactly" the mechanism of the problem yet, since it will not likely show up on a small sized program that has less structure in it. This makes it hard to document expect in a very large program (which some programmers cannot give out the code).
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