waf: compiler flags, uninitalized variable

[Hal Murray]

Thanks.  I was hoping that somebody would be familiar with this area and 
just recognize what was going on.


> Usually, you won't get that type of warning unless you enable it.  And
> usually, you only get that type of warning in an optimized compile, since
>  the dataflow analysis needed to detect it is part of the optimization
> code.

gcc (GCC) 15.1.1 20250521 (Red Hat 15.1.1-2)

No error or warning.

Here is output from waf build -v

00:12:34 runner ['/usr/sbin/gcc', '-DUNITY_EXCLUDE_FLOAT_PRINT', 
'-Wshadow', '-Wpacked', '-Wcast-qual', '-Wmissing-declarations', 
'-Wdisabled-optimization', '-Wimplicit-function-declaration', 
'-Winvalid-pch', '-Wpointer-arith', '-Wwrite-strings', '-Winit-self', 
'-Wfloat-equal', '-Wformat', '-Wformat-signedness', '-Wformat-security', 
'-Wsuggest-attribute=noreturn', '-Wimplicit-fallthrough=3', '-fPIC', 
'-O1', '-Wall', '-Wextra', '-Wmissing-prototypes', '-Wstrict-prototypes', 
'-Wundef', '-Wunused', '-Winline', '-Wswitch-default', '-Wswitch-enum', 
'-g', '-std=c99', '-D_GNU_SOURCE', '-I..', '-Iinclude', '-I../../include', 
'-Ilibaes_siv', '-I../../libaes_siv', '-I/usr/local/ssl/include', 
'-DPYTHONDIR="/usr/local/lib/python3.13/site-packages"', 
'-DPYTHONARCHDIR="/usr/local/lib/python3.13/site-packages"', 
'../../attic/tls-tester.c', '-c', '-o/home/murray/ntpsec/play/hgm/main/atti
c/tls-tester.c.14.o']

The man page says -Wuninitialized and -Wmaybe-uninitialized are both 
enabled by -Wall and also -Wextra

--------

cc (Debian 12.2.0-14+deb12u1) 12.2.0
../../attic/tls-tester.c:165:10: warning: \u2018sent\u2019 may be used 
uninitialized [-Wmaybe-uninitialized]


cc (Debian 8.3.0-6) 8.3.0
../../attic/tls-tester.c:165:10: warning: \u2018sent\u2019 may be used 
uninitialized in this function [-Wmaybe-uninitialized]


cc (Ubuntu 9.4.0-1ubuntu1~20.04.2) 9.4.0
../../attic/tls-tester.c:165:10: warning: \u2018sent\u2019 may be used 
uninitialized in this function [-Wmaybe-uninitialized]

cc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
../../attic/tls-tester.c:165:10: warning: \u2018sent\u2019 may be used 
uninitialized in this function [-Wmaybe-uninitialized]

cc (Ubuntu 14.2.0-19ubuntu2) 14.2.0
no error or warning


NetBSD:
cc (nb3 20231008) 10.5.0
../../attic/tls-tester.c:165:8: warning: \u2018sent\u2019 may be used 
uninitialized in this function [-Wmaybe-uninitialized]

cc (nb4 20200810) 7.5.0
../../attic/tls-tester.c:165:8: warning: \u2018sent\u2019 may be used 
uninitialized in this function [-Wmaybe-uninitialized]


FreeBSD clang version 19.1.7
../../attic/tls-tester.c:165:12: warning: variable 'sent' is uninitialized 
when used here [-Wuninitialized]


cc (Raspbian 12.2.0-14+rpi1) 12.2.0
../../attic/tls-tester.c:165:10: warning: \u2018sent\u2019 may be used 
uninitialized [-Wmaybe-uninitialized]




If anybody wants to play, here is the edit to put the bug back in:

diff --git a/attic/tls-tester.c b/attic/tls-tester.c
index adbce9a84..3c57fdc0e 100644
--- a/attic/tls-tester.c
+++ b/attic/tls-tester.c
@@ -162,7 +162,7 @@ static int chunkify(SSL *ssl, uint8_t *buff, int 
bytes) {
   while (0<bytes) {
     int to_send, sent;
     to_send = random() % (bytes+1);
-    if (0==total && to_send==bytes) {
+    if (0==sent && to_send==bytes) {
       /* avoid all in one chunk */
       continue;
     }


-- 
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