[bootlin/training-materials updates] master: sysdev/sysdev-thirdparty: add hint to allow the build of libgpiod to work (57ce7aa2)

[Thomas Petazzoni]

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/57ce7aa223f8b19acc0b4381a1f84a4cb2754df3

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commit 57ce7aa223f8b19acc0b4381a1f84a4cb2754df3
Author: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
Date:   Tue Sep 27 22:01:42 2022 +0200

    sysdev/sysdev-thirdparty: add hint to allow the build of libgpiod to work
    
    Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>


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57ce7aa223f8b19acc0b4381a1f84a4cb2754df3
 labs/sysdev-thirdparty/sysdev-thirdparty.tex | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/labs/sysdev-thirdparty/sysdev-thirdparty.tex b/labs/sysdev-thirdparty/sysdev-thirdparty.tex
index 99a0b3f5..a6364f15 100644
--- a/labs/sysdev-thirdparty/sysdev-thirdparty.tex
+++ b/labs/sysdev-thirdparty/sysdev-thirdparty.tex
@@ -622,6 +622,14 @@ Now, compile the software:
 
 \bashcmd{$ make}
 
+The build will probably fail with {\em undefined reference to
+`rpl\_malloc'}. This is due to a test in the configure script that
+requires running a test program, which doesn't work when
+cross-compiling. We can preseed the result of this test by passing
+\code{ac_cv_func_malloc_0_nonnull=yes}:
+
+\bashcmd{$ ac_cv_func_malloc_0_nonnull=yes CC=arm-linux-gcc ./configure --host=arm-linux --prefix=/usr --enable-tools}
+
 Installation to the {\em staging} space can be done using the
 classical \code{DESTDIR} mechanism: