From: Paul Floyd <pjfloyd@wanadoo.fr>
Date: Sat, 28 Sep 2024 06:20:25 +0000 (+0200)
Subject: Compiler warning in ML_(check_elf_and_get_rw_loads)
X-Git-Tag: VALGRIND_3_24_0~61
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9626d20f0151c1b34d511c82796d7b34aabc5939;p=thirdparty%2Fvalgrind.git

Compiler warning in ML_(check_elf_and_get_rw_loads)

GCC 12.2 complains that
 previous_rw_a_phdr.p_vaddr + previous_rw_a_phdr.p_filesz
may be using p_filesz uninitialized

That's only possible if ML_(img_get) somehow fails to read all
of a program header such that p_memsz is greater than 0 but
p_filesz remains uninitialized. Hardly likely since p_memsz
comes after p_filesz in the structure.
---

diff --git a/coregrind/m_debuginfo/readelf.c b/coregrind/m_debuginfo/readelf.c
index b037b9201..1d6ec55a0 100644
--- a/coregrind/m_debuginfo/readelf.c
+++ b/coregrind/m_debuginfo/readelf.c
@@ -3902,6 +3902,8 @@ Bool ML_(check_elf_and_get_rw_loads) ( Int fd, const HChar* filename,
 
    /* Sets p_memsz to 0 to indicate we have not yet a previous a_phdr. */
    previous_rw_a_phdr.p_memsz = 0;
+   /* and silence compiler warnings */
+   previous_rw_a_phdr.p_filesz = 0;
 
    for (i = 0U; i < phdr_mnent; i++) {
       ElfXX_Phdr a_phdr;