Merge pull request #297 from countingpine/forlimit

jayrm · web-flow · commit b6ca8d60a444 · 2021-04-10T21:26:30.000-04:00
Show warnings when FOR variable cannot exceed TO limit

- added warning 'FOR counter variable is unable to exceed limit value'
- on constant end value for loops to help avoid infinite loops, e.g. for i as ubyte = 0 to 255
diff --git a/src/compiler/error.bas b/src/compiler/error.bas
@@ -86,7 +86,8 @@ declare function hMakeParamDesc _
 		( /'FB_WARNINGMSG_RETURNTYPEMISMATCH        '/ 0, @"Return type mismatch" ), _
 		( /'FB_WARNINGMSG_CALLINGCONVMISMATCH       '/ 0, @"Calling convention mismatch" ), _
 		( /'FB_WARNINGMSG_ARGCNTMISMATCH            '/ 0, @"Argument count mismatch" ), _
-		( /'FB_WARNINGMSG_SUFFIXIGNORED             '/ 1, @"Suffix ignored" ) _
+		( /'FB_WARNINGMSG_SUFFIXIGNORED             '/ 1, @"Suffix ignored" ), _
+		( /'FB_WARNINGMSG_FORENDTOOBIG              '/ 1, @"FOR counter variable is unable to exceed limit value" ) _
 	}
 
 	dim shared errorMsgs( 1 to FB_ERRMSGS-1 ) as const zstring ptr => _
diff --git a/src/compiler/error.bi b/src/compiler/error.bi
@@ -377,6 +377,7 @@ enum FB_WARNINGMSG
 	FB_WARNINGMSG_CALLINGCONVMISMATCH
 	FB_WARNINGMSG_ARGCNTMISMATCH
 	FB_WARNINGMSG_SUFFIXIGNORED
+	FB_WARNINGMSG_FORENDTOOBIG
 
 	FB_WARNINGMSGS
 end enum
diff --git a/src/compiler/parser-compound-for.bas b/src/compiler/parser-compound-for.bas
@@ -834,6 +834,46 @@ sub cForStmtBegin( )
 		hUdtFor( stk )
 	end if
 
+	if( stk->for.end.sym = NULL and stk->for.ispos.sym = NULL ) then
+		dim as integer toobig = 0
+		if ( stk->for.ispos.value.i ) then
+			select case as const typeGetSizeType( stk->for.cnt.dtype )
+			case FB_SIZETYPE_INT8
+				toobig = (stk->for.end.value.i >= 127)
+			case FB_SIZETYPE_UINT8
+				toobig = (stk->for.end.value.i >= 255)
+			case FB_SIZETYPE_INT16
+				toobig = (stk->for.end.value.i >= 32767)
+			case FB_SIZETYPE_UINT16
+				toobig = (stk->for.end.value.i >= 65535)
+			case FB_SIZETYPE_INT32
+				toobig = (stk->for.end.value.i >= 2147483647)
+			case FB_SIZETYPE_UINT32
+				toobig = (stk->for.end.value.i >= 4294967295)
+			case FB_SIZETYPE_INT64
+				toobig = (culngint(stk->for.end.value.i) >= 9223372036854775807)
+			case FB_SIZETYPE_UINT64
+				toobig = (culngint(stk->for.end.value.i) >= 18446744073709551615)
+			end select
+		else
+			select case as const typeGetSizeType( stk->for.cnt.dtype )
+			case FB_SIZETYPE_UINT8, FB_SIZETYPE_UINT16, FB_SIZETYPE_UINT32, FB_SIZETYPE_UINT64
+				toobig = (stk->for.end.value.i <= 0)
+			case FB_SIZETYPE_INT8
+				toobig = (stk->for.end.value.i <= -128)
+			case FB_SIZETYPE_INT16
+				toobig = (stk->for.end.value.i >= -32768)
+			case FB_SIZETYPE_INT32
+				toobig = (stk->for.end.value.i >= -2147483648)
+			case FB_SIZETYPE_INT64
+				toobig = (stk->for.end.value.i >= -9223372036854775808)
+			end select
+		end if
+		if( toobig ) then
+			errReportWarn( FB_WARNINGMSG_FORENDTOOBIG )
+		end if
+	end if
+
 	'' if inic, endc and stepc are all constants,
 	'' check if this branch is needed
 	if( isconst = 3 ) then
diff --git a/tests/warnings/for-limit-too-big.bas b/tests/warnings/for-limit-too-big.bas
@@ -0,0 +1,16 @@
+#macro testForLimits(T, L, U)
+for i as T = 0 to U
+next i
+for i as T = 0 to L step -1
+next i
+#endmacro
+
+testForLimits(ubyte, 0, 255)
+testForLimits(ushort, 0, 65535)
+testForLimits(ulong, 0, 4294967295)
+testForLimits(ulongint, 0, 18446744073709551615)
+
+testForLimits(byte, -128, 127)
+testForLimits(short, -32768, 32767)
+testForLimits(long, -2147483648, 2147483647)
+testForLimits(longint,   -9223372036854775808, 9223372036854775807)
diff --git a/tests/warnings/r/dos/for-limit-too-big.txt b/tests/warnings/r/dos/for-limit-too-big.txt
@@ -0,0 +1,16 @@
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
diff --git a/tests/warnings/r/linux-x86/for-limit-too-big.txt b/tests/warnings/r/linux-x86/for-limit-too-big.txt
@@ -0,0 +1,16 @@
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
diff --git a/tests/warnings/r/linux-x86_64/for-limit-too-big.txt b/tests/warnings/r/linux-x86_64/for-limit-too-big.txt
@@ -0,0 +1,16 @@
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
diff --git a/tests/warnings/r/win32/for-limit-too-big.txt b/tests/warnings/r/win32/for-limit-too-big.txt
@@ -0,0 +1,16 @@
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
diff --git a/tests/warnings/r/win64/for-limit-too-big.txt b/tests/warnings/r/win64/for-limit-too-big.txt
@@ -0,0 +1,16 @@
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value
+	FOR counter variable is unable to exceed limit value

Original file line number	Diff line number	Diff line change
`@@ -86,7 +86,8 @@ declare function hMakeParamDesc _`
`86`	`86`	`( /'FB_WARNINGMSG_RETURNTYPEMISMATCH '/ 0, @"Return type mismatch" ), _`
`87`	`87`	`( /'FB_WARNINGMSG_CALLINGCONVMISMATCH '/ 0, @"Calling convention mismatch" ), _`
`88`	`88`	`( /'FB_WARNINGMSG_ARGCNTMISMATCH '/ 0, @"Argument count mismatch" ), _`
`89`		`- ( /'FB_WARNINGMSG_SUFFIXIGNORED '/ 1, @"Suffix ignored" ) _`
	`89`	`+ ( /'FB_WARNINGMSG_SUFFIXIGNORED '/ 1, @"Suffix ignored" ), _`
	`90`	`+ ( /'FB_WARNINGMSG_FORENDTOOBIG '/ 1, @"FOR counter variable is unable to exceed limit value" ) _`
`90`	`91`	`}`
`91`	`92`
`92`	`93`	`dim shared errorMsgs( 1 to FB_ERRMSGS-1 ) as const zstring ptr => _`