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When passing NULL to ezxml_set_attr I am getting a segfault, even though in file itself it says that passing NULL would remove tag.

Hope to hear from you soon,

Thanks in advance.

Please

Summary

Compilation warning arise in ezxml.c for gcc-7 compiler to compare between signed integer(-1) and unsigned variable (root->len) within function void ezxml_free(ezxml_t xml).

It raises an -Wsign-compare warning in gcc-7.

Steps to reproduce

The environment is under CentOS Linux release 7.9.2009 (Core), with gcc (GCC) 7.3.0.

Compilation rules were defined as below, with ezxml.h located in ${PROJECT_BINARY_DIR} and ezxml.c in the same directory with CMakeList.txt. ( same with #6 )

project(APP C)
include_directories(${PROJECT_BINARY_DIR})

# source files
set(CLI_SRC ezxml.c)

add_executable(APP ${CLI_SRC})
...

What is the current bug(warning) behavior?

gcc shows warning as below:

[ 85%] Building C object cli/CMakeFiles/ezxml.c.o
/home/cli/ezxml.c: In function 'ezxml_free':
/home/cli/ezxml.c:813:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (root->len == -1) free(root->m);
                       ^

Possible fixes

My suggestion would be add a type conversion such as

if (root->len == (unsigned int)-1) free(root->m); // malloced xml data

Instead of

if (root->len == -1) free(root->m); // malloced xml data

Labels

/label ~bug ~reproduced ~needs-investigation

Summary

Compilation warning arise in ezxml.c for gcc compiler to parse an inline expression of condition which breaks a while loop.

The code snippet triggering the warning took place in line 364, inside function ezxml_internal_dtd(), which aims to parse default attributes such as .

Steps to reproduce

The environment is under CentOS Linux release 7.9.2009 (Core), with gcc (GCC) 7.3.0.

Compilation rules were defined ias below, with ezxml.h located in ${PROJECT_BINARY_DIR} and ezxml.c in the same directory with CMakeList.txt.

project(APP C)
include_directories(${PROJECT_BINARY_DIR})

# source files
set(CLI_SRC ezxml.c)

add_executable(APP ${CLI_SRC})
...

What is the current bug(warning) behavior?

gcc shows warning as below:

[ 85%] Building C object cli/CMakeFiles/ezxml.c.o
/home/cli/ezxml.c: In function 'ezxml_internal_dtd':
/home/cli/ezxml.c:364:26: warning: operation on 's' may be undefined [-Wsequence-point]
             while (*(n = ++s + strspn(s, EZXML_WS)) && *n != '>') {
                          ^

Possible fixes

My suggestion would be removing the inline condition expression, and adopting an multi-line expression instead.

Such as

while (*n != '>') {
                ++s;
                if (*(n = s + strspn(s, EZXML_WS)) == 0) { break; }
                ...

Labels

/label ~bug ~reproduced ~needs-investigation

I suggest inserting these lines in ezxml.c

#ifdef _WIN32
#define EZXML_NOMMAP
#endif