Installing LAPACK

Procedure

Use PuTTY to log in to the server as the root user.
Decompress the LAPACK installation package.
```
tar -xvf lapack-3.8.0.tar.gz
```
Go to the directory generated after the decompression.
```
cd lapack-3.8.0
```
Generate a make.inc file.
```
cp make.inc.example make.inc
```
Edit the make.inc file.
1. Open the make.inc file.
```
vi make.inc
```
2. Press i to enter the edit mode and modify the file as follows:
  Modify the content in line 11 to the following:
```
CC = clang
```
  Modify the content in line 22 to the following:
```
FORTRAN = flang
```
  Modify the content in line 30 to the following:
```
LOADER = flang
```
  Modify the content in line 81 to the following:
```
libblas.a
```
  After performing 5.a, press Esc, type :set nu, and press Enter to display the line number.
3. Press Esc, type :wq!, and press Enter to save the file and exit.
Edit the INSTALL/second_INT_ETIME.f file.
1. Open the INSTALL/second_INT_ETIME.f file.
```
vi INSTALL/second_INT_ETIME.f
```
2. Press i to enter the edit mode and add the following function below line 35 in the second_INT_ETIME.f file.
```
REAL Function etime(time)
REAL time(2)
Call Cpu_Time(etime)
time(1) = etime
time(2) = 0
End Function
```
  *Comment out the following lines:
```
*REAL        ETIME
*INTRINSIC   ETIME
```
  After performing 6.a, press Esc, type :set nu, and press Enter to display the line number.
3. Press Esc, type :wq!, and press Enter to save the file and exit.
Edit the INSTALL/dsecnd_INT_ETIME.f file.
1. Open the INSTALL/dsecnd_INT_ETIME.f file.
```
vi INSTALL/dsecnd_INT_ETIME.f
```
2. Press i to enter the edit mode and add the following function below line 35 in the dsecnd_INT_ETIME.f file.
```
REAL Function etime(time)
REAL time(2)
Call Cpu_Time(etime)
time(1) = etime
time(2) = 0
End Function
```
  *Comment out the following lines:
```
*REAL        ETIME
*INTRINSIC   ETIME
```
  After performing 7.a, press Esc, type :set nu, and press Enter to display the line number.
3. Press Esc, type :wq!, and press Enter to save the file and exit.
Perform the installation.
```
make -j
```
Copy the static library to another directory.
```
cp *.a /path/to/EXTRA/mathlib
```

Parent topic: Configuring the Compilation Environment