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Various fixes thanks to @bgenia
- Add $(MAKEFLAGS) - Add clarification on importance of the order of flags while linking with library.
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‎README.md

+43-35
Original file line numberDiff line numberDiff line change
@@ -131,7 +131,7 @@ used for **all the other lines**.
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About the **equal signs**:
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134-
- `:=` **simply expand** the defined variable (like C equal sign).
134+
- `:=` **simply expand** the defined variable (like C `=`).
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- `=` **recursively expand** the defined variable (the expression is expanded
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afterward, when (and each time) the variable is used).
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@@ -163,7 +163,7 @@ all:
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[**Version 1 / Simplest C project**](#version-1)
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> - 42 C coding style conventions
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> - `MAKE` predefined variable
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> - builtin variables
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> - The C compilation implicit rule
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> - pattern rule contains `%` character
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> - Automatic variables in practice
@@ -202,7 +202,8 @@ all:
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> - `addprefix` make function
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> - flags and libraries used by the linker
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> - `dir` function
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> - Compiling with a library recap
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> - Build with a library
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> - Linking with a library
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> - builds each of the required libraries
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> - call rules recursively
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@@ -231,7 +232,7 @@ The simplest, build a program called `icecream` with the following structure:
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### v1 Brief
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- 42 C coding style conventions
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- `MAKE` predefined variable
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- builtin variables
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- The C compilation implicit rule
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- pattern rule contains `%` character
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- Automatic variables in practice
@@ -266,9 +267,10 @@ CFLAGS := -Wall -Wextra -Werror
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
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# MAKEFLAGS make flags
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RM := rm -f
271-
MAKE := $(MAKE) --no-print-directory
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MAKEFLAGS += --no-print-directory
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#------------------------------------------------#
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# RECIPES #
@@ -303,20 +305,23 @@ re:
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####################################### END_1 ####
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```
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306-
- The choice of the `CC` and `CFLAGS` values, `$(NAME)`, `clean`, `fclean`,
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`all` and `re` as the basic rules as well as not using a wildcard to auto
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generate the sources list is guided by the **42 C coding style conventions**,
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do not hesitate to disagree and change it (like renaming `clean` and `fclean`
310-
to the more GNU conventional `mostlyclean` and `clean` respectively).
308+
- The choice of the `CC` and `CFLAGS` values, `NAME`, `clean`, `fclean`, `all`
309+
and `re` as the basic rules as well as not using a wildcard to auto generate
310+
the sources list is guided by the **42 C coding style conventions**, do not
311+
hesitate to disagree and change it (like renaming `clean` and `fclean` to the
312+
more GNU conventional `mostlyclean` and `clean` respectively).
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312314
<sub><sub><hr></sub></sub>
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314-
- **`MAKE`** is a **predefined variable** whose value corresponds to the make
315-
executable being run, for this reason we choose to increment its options.
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When a Makefile is executed from another Makefile, the called's `MAKE`
317-
variable inherit from the caller's `MAKE` value. We pass it the
318-
`--no-print-directory` flag for a cleaner output, try to remove it and run
319-
`make` to see the difference.
316+
- `MAKE` and `MAKEFLAGS` are **builtin variables** like `CFLAGS` and a lot of
317+
others that you can find in the *data-base* (`make --print-data-base`
318+
command). `MAKE` value corresponds to the `make` executable being run and
319+
`MAKEFLAGS` to its flags. When a Makefile is executed from another Makefile,
320+
the called's `MAKE` `MAKEFLAGS` variables inherit from the caller's `MAKE`
321+
`MAKEFLAGS` values.
322+
323+
Here we append `--no-print-directory` to `MAKEFLAGS` content to have a clearer
324+
output, try to remove it and `make re` to see the difference.
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321326
<sub><sub><hr></sub></sub>
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@@ -331,8 +336,8 @@ Where `%.o` expands to each objects, `%.c` to each sources, `$@` to the first
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target (which is `%.o`) and `$<` to the leftmost prerequisite (which is `%.c`).
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*As their name implies implicit rules are implicit and do not need to be
334-
written. All the implicit rules can be found in the data-base, accessible
335-
with a `make -p -f/dev/null | less` shell command.*
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written. As well as the builtin variables, all the implicit rules can be found
340+
in the data-base, accessible with `make -p -f/dev/null | less` command.*
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<sub><sub><hr></sub></sub>
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@@ -485,10 +490,10 @@ CPPFLAGS := -I .
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
488-
# MAKE quietly make
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# MAKEFLAGS make flags
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490495
RM := rm -f
491-
MAKE := $(MAKE) --no-print-directory
496+
MAKEFLAGS += --no-print-directory
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493498
#------------------------------------------------#
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# RECIPES #
@@ -650,11 +655,11 @@ CPPFLAGS := -I include
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
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# MAKE quietly make
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# MAKEFLAGS make flags
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# DIR_DUP duplicate directory tree
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656661
RM := rm -f
657-
MAKE := $(MAKE) --no-print-directory
662+
MAKEFLAGS += --no-print-directory
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DIR_DUP = mkdir -p $(@D)
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```
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@@ -832,11 +837,11 @@ main.o: main.c main.o: main.c icecream.h
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
835-
# MAKE quietly make
840+
# MAKEFLAGS make flags
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# DIR_DUP duplicate directory tree
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838843
RM := rm -f
839-
MAKE := $(MAKE) --no-print-directory
844+
MAKEFLAGS += --no-print-directory
840845
DIR_DUP = mkdir -p $(@D)
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842847
#------------------------------------------------#
@@ -954,7 +959,8 @@ Builds an `icecream` **program that uses** `libbase` and `libarom`
954959
- `addprefix` make function
955960
- flags and libraries used by the linker
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- `dir` function
957-
- Compiling with a library recap
962+
- Build with a library
963+
- Linking with a library
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- builds each of the required libraries
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- call rules recursively
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@@ -1026,8 +1032,8 @@ LDLIBS := $(addprefix -l,$(LIBS))
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<sub><sub><hr></sub></sub>
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1029-
- `LDFLAGS` and `LDLIBS` contains the **flags and libraries** that will be
1030-
**used by the linker** `ld` to link the library to our project sources.
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- `LDFLAGS` and `LDLIBS` contain the **flags and libraries** that will be **used
1036+
by the linker** `ld` to link the library to our project sources.
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10321038
<sub><sub><hr></sub></sub>
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@@ -1037,12 +1043,9 @@ LDLIBS := $(addprefix -l,$(LIBS))
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10381044
<sub><sub><hr></sub></sub>
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1040-
- **Compiling with a library recap**:
1041-
1042-
Compiling with a library requires, in addition to a C project and a library, a
1043-
`-I` flag that indicates to the compiler where to find the library header files,
1044-
`-L` indicate to the linker where to find the library and `-l` the name of this
1045-
library (conventionally: lib<name>).
1046+
- **Build with a library** requires three flags: `-I` tell the compiler where to
1047+
find the lib header files, `-L` tells the linker where to look for the library
1048+
and `-l` the name of this library (without its conventional `lib` prefix).
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10471050
For example: `-I lib/libarom/include -L lib/libarom -l arom`
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@@ -1052,11 +1055,11 @@ For example: `-I lib/libarom/include -L lib/libarom -l arom`
10521055
# UTENSILS #
10531056
#------------------------------------------------#
10541057
# RM force remove
1055-
# MAKE quietly make
1058+
# MAKEFLAGS make flags
10561059
# DIR_DUP duplicate directory tree
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10581061
RM := rm -f
1059-
MAKE := $(MAKE) --silent --no-print-directory
1062+
MAKEFLAGS += --silent --no-print-directory
10601063
DIR_DUP = mkdir -p $(@D)
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10621065
#------------------------------------------------#
@@ -1101,6 +1104,11 @@ re:
11011104
$(MAKE) all
11021105
```
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1107+
- **Linking with a library** requires special attention to the order of the
1108+
linking flags. In our case we need to make sure that `$(LDFLAGS)` and
1109+
`$(LDLIBS)` passes respectively before and after the `$(OBJS)` in the linking
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recipe.
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11041112
- `$(LIBS_TARGET)` rule **builds each of the required libraries** found in the
11051113
`INGREDIENTS` part. It is a `$(NAME)` prerequisite for the same reason as
11061114
`$(OBJS)` because our *final goal* needs the libraries as well as the objects

‎projects/v1/Makefile

+2-2
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@@ -22,10 +22,10 @@ CFLAGS := -Wall -Wextra -Werror
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
25-
# MAKE quietly make
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# MAKEFLAGS make flags
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2727
RM := rm -f
28-
MAKE := $(MAKE) --no-print-directory
28+
MAKEFLAGS += --no-print-directory
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3030
#------------------------------------------------#
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# RECIPES #

‎projects/v2/Makefile

+2-2
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@@ -24,10 +24,10 @@ CPPFLAGS := -I .
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
27-
# MAKE quietly make
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# MAKEFLAGS make flags
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2929
RM := rm -f
30-
MAKE := $(MAKE) --no-print-directory
30+
MAKEFLAGS += --no-print-directory
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3232
#------------------------------------------------#
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# RECIPES #

‎projects/v3/Makefile

+2-2
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@@ -33,11 +33,11 @@ CPPFLAGS := -I include
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
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# MAKE quietly make
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# MAKEFLAGS make flags
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# DIR_DUP duplicate directory tree
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3939
RM := rm -f
40-
MAKE := $(MAKE) --no-print-directory
40+
MAKEFLAGS += --no-print-directory
4141
DIR_DUP = mkdir -p $(@D)
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4343
#------------------------------------------------#

‎projects/v4/Makefile

+2-2
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@@ -38,11 +38,11 @@ ARFLAGS := -r -c -s
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
41-
# MAKE quietly make
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# MAKEFLAGS make flags
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# DIR_DUP duplicate directory tree
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4444
RM := rm -f
45-
MAKE := $(MAKE) --no-print-directory
45+
MAKEFLAGS += --no-print-directory
4646
DIR_DUP = mkdir -p $(@D)
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4848
#------------------------------------------------#

‎projects/v5/Makefile

+5-2
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@@ -51,11 +51,11 @@ LDLIBS := $(addprefix -l,$(LIBS))
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
54-
# MAKE quietly make
54+
# MAKEFLAGS make flags
5555
# DIR_DUP duplicate directory tree
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5757
RM := rm -f
58-
MAKE := $(MAKE) --silent --no-print-directory
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MAKEFLAGS += --silent --no-print-directory
5959
DIR_DUP = mkdir -p $(@D)
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6161
#------------------------------------------------#
@@ -99,6 +99,9 @@ re:
9999
$(MAKE) fclean
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$(MAKE) all
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102+
info-%:
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$(MAKE) --dry-run --always-make $* | grep -v "info"
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#------------------------------------------------#
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# SPEC #
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#------------------------------------------------#

‎projects/v5/lib/libarom/Makefile

+2-2
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@@ -37,11 +37,11 @@ ARFLAGS := -r -c -s
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# UTENSILS #
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#------------------------------------------------#
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# RM force remove
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# MAKE quietly make
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# MAKEFLAGS make flags
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# DIR_DUP duplicate directory tree
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4343
RM := rm -f
44-
MAKE := $(MAKE) --no-print-directory
44+
MAKEFLAGS += --no-print-directory
4545
DIR_DUP = mkdir -p $(@D)
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4747
#------------------------------------------------#

‎projects/v5/lib/libbase/Makefile

+2-2
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@@ -37,11 +37,11 @@ ARFLAGS := -r -c -s
3737
# UTENSILS #
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#------------------------------------------------#
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# RM force remove
40-
# MAKE quietly make
40+
# MAKEFLAGS make flags
4141
# DIR_DUP duplicate directory tree
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4343
RM := rm -f
44-
MAKE := $(MAKE) --no-print-directory
44+
MAKEFLAGS += --no-print-directory
4545
DIR_DUP = mkdir -p $(@D)
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4747
#------------------------------------------------#

‎projects/v5/src/main.c

+2-2
Original file line numberDiff line numberDiff line change
@@ -2,14 +2,14 @@
22

33
int main(void)
44
{
5-
write (1, "\n ICECREAM\n", 18);
5+
write (1, "\n ICECREAM\n\n", 18);
66
write (1, " [From lib base]\n\n", 21);
77
base_milk();
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base_water();
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write (1, "\n [From lib arom]\n\n", 22);
1010
arom_coco();
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arom_cherry();
1212
write (1, "\n [From lib m]\n\n", 19);
13-
dprintf(2, "m: pow(2,2) = %f\n\n", pow(2,2));
13+
printf("m: pow(2,2) = %f\n\n", pow(2,2));
1414
return (0);
1515
}

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