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MESC TOOL NEWS:
MESCT-NC30WA_2-000901D
NC30WA V.4.00 Release 1
Precaution
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Please take note of the following problems in using C compiler NC30WA for the M16C/60 and 20 series of MCUs (with an assembler and integrated development environment):
- If a result of operation using an & operator is evaluated, incorrect code may be generated.
- If a multiply operation includes a floating-point number, System Error may arise or incorrect code may be generated.
- If both a void function and an inline function are contained in a file, incorrect code may be generated.
- If a result of operation using an & operator is evaluated, incorrect code may be generated.
- 1.1 Conditions
- This problem occurs if the following six conditions are satisfied:
- (1) A variable of type char or int that is bitwise-ANDed with immediate value A is tested for its equality or inequality to another
immediate value B.
- (2) Immediate value A has more than one 1's bit.
- (3) Immediate value B is not 0.
- (4) The test is done with "equal to" operator "==" or "not equal to" operator "!=".
- (5) The program statement executed if the result of the test is TRUE is a single assignment of immediate value C to a variable of type char.
- (6) No else statement exists.
- 1.2 Example
-
--------------------------------------------------------------------
if( (i&0x0005)==0x0003){
c=1;
}
--------------------------------------------------------------------
- * In the above example, immediate value A is 0x0005, immediate value B is 0x0003, and immediate value C is 1.
- 1.3 Workaround
- Place a dummy "asm" function immediately before the program statement executed if the test is TRUE as follows:
-
--------------------------------------------------------------------
if((i&0x0005)==0x0003){
asm(); /* A dummy "asm" function */
c=1;
}
--------------------------------------------------------------------
- 1.4 Schedule of Fixing Problem
- We plan to fix this problem in our next release.
NC30WA V.4.00 Release 1 Precaution
MESCT-NC30WA_2-000901D
- If a multiply operation includes a floating-point number, System Error may arise or incorrect code may be generated.
- 2.1 Conditions
This problem occurs if the following two conditions are satisfied:
- (1) In a multiply operation, either a multiplier or a multiplicand is a floating-point number.
- (2) Optimize option -OS is used.
- 2.2 Workaround
- If floating-point numbers are included, use any of the other optimize options than -OS.
- 2.3 Schedule of Fixing Problem
- We plan to fix this problem in our next release.
NC30WA V.4.00 Release 1 Precaution
MESCT-NC30WA_2-000901D
- If both a void function and an inline function are contained in a file, incorrect code may be generated.
- 3.1 Conditions
- This problem occurs if the following three conditions are satisfied:
- (1) A void function or an inline function are contained in a file.
- (2) A function that calls the void function or the inline functions only is contained in the above file.
- (3) Any of optimize options -OR, -O[3-5], and -OS is used at compilation.
- 3.2 Example
--------------------------------------------------------------------
void func(void){ /* Void function */
}
inline void inline_func(void){ /* inline function */
:
}
void inline_call(void){ /* Function calling inline function only */
inline_func();
}
--------------------------------------------------------------------
- 3.3 Workaround
- Use compile option-Ono_asmopt or -ONA together with the already-selected option.
- 3.4 Schedule of Fixing Problem
- We plan to fix this problem in our next release.
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